0000950170-24-056459 | 10-Q | XBRL Viewer

Three Months Ended March 31,

Equity compensation

Restricted stock

Anti-dilutive shares excluded from computation of earnings per share

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Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net income	$ 131.6	$ 117.4
Other comprehensive income (loss), net of tax:
Net unrealized gains (losses) on commodity derivatives (net of tax of $0.0 and $0.3, respectively)	(0.1)	(0.9)
Other comprehensive income, net of tax	2.5	1.2
Comprehensive income	134.1	118.6
Less: comprehensive income attributable to non-controlling interest	(3.7)	(3.3)
Comprehensive income available for common stock	130.4	115.3
Interest rate swaps
Other comprehensive income (loss), net of tax:
Other comprehensive income (loss), cash flow hedge, gain (loss), reclassification, after tax	0.6	0.6
Commodity derivatives
Other comprehensive income (loss), net of tax:
Other comprehensive income (loss), cash flow hedge, gain (loss), reclassification, after tax	$ 2.0	$ 1.5

Commitment, Contingencies And Guarantees	3 Months Ended
Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	(3) Commitments, Contingencies and Guarantees There have been no significant changes to commitments, contingencies and guarantees from those previously disclosed in Note 3 of our Notes to the Consolidated Financial Statements in our 2023 Annual Report on Form 10-K.

Commitment, Contingencies And Guarantees

3 Months Ended

Mar. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Commitments, Contingencies and Guarantees

(3)

Commitments, Contingencies and Guarantees

There have been no significant changes to commitments, contingencies and guarantees from those previously disclosed in Note 3 of our Notes to the Consolidated Financial Statements in our 2023 Annual Report on Form 10-K.

Business Segment Information - Additional Information (Details)	3 Months Ended
	Mar. 31, 2024 Segment
Segment Reporting Information, Additional Information [Abstract]
Number of operating segments	2

Fair Value Measurements

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

(8)

Fair Value Measurements

We use the following fair value hierarchy for determining inputs for our financial instruments. Our assets and liabilities for financial instruments are classified and disclosed in one of the following fair value categories:

Level 1 — Unadjusted quoted prices available in active markets that are accessible at the measurement date for identical unrestricted assets or liabilities. Level 1 instruments primarily consist of highly liquid and actively traded financial instruments with quoted pricing information on an ongoing basis.

Level 2 — Pricing inputs include quoted prices for identical or similar assets and liabilities in active markets other than quoted prices in Level 1, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means.

Level 3 — Pricing inputs are generally less observable from objective sources. These inputs reflect management’s best estimate of fair value using its own assumptions about the assumptions a market participant would use in pricing the asset or liability.

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement within the fair value hierarchy levels. We record transfers, if necessary, between levels at the end of the reporting period for all of our financial instruments.

Transfers into Level 3, if any, occur when significant inputs used to value the derivative instruments become less observable, such as a significant decrease in the frequency and volume in which the instrument is traded, negatively impacting the availability of observable pricing inputs. Transfers out of Level 3, if any, occur when the significant inputs become more observable, such as when the time between the valuation date and the delivery date of a transaction becomes shorter, positively impacting the availability of observable pricing inputs.

Recurring Fair Value Measurements

Derivatives

The commodity contracts for our Utilities segments are valued using the market approach and include forward strip pricing at liquid delivery points, exchange-traded futures, options, basis swaps and over-the-counter swaps and options (Level 2) for wholesale electric energy and natural gas contracts. For exchange-traded futures, options and basis swap assets and liabilities, fair value was derived using broker quotes validated by the exchange settlement pricing for the applicable contract. For over-the-counter instruments, the fair value is obtained by utilizing a nationally recognized service that obtains observable inputs to compute the fair value, which we validate by comparing our valuation with the counterparty. The fair value of these swaps includes a credit valuation adjustment based on the credit spreads of the counterparties when we are in an unrealized gain position or on our own credit spread when we are in an unrealized loss position. For additional information, see Note 1 of our Notes to the Consolidated Financial Statements in our 2023 Annual Report on Form 10-K.

The following tables set forth, by level within the fair value hierarchy, our gross assets and gross liabilities and related offsetting as permitted by GAAP that were accounted for at fair value on a recurring basis for derivative instruments.


	As of March 31, 2024
	Level 1		Level 2		Level 3		Cash Collateral and Counterparty Netting (a)		Total
	(in millions)
Assets:
Commodity derivatives - Gas Utilities	$	-	$	-	$	-			$	-
Total	$	-	$	-	$	-	$	-	$	-

Liabilities:
Commodity derivatives - Gas Utilities	$	-	$	2.1	$	-			$	2.1
Total	$	-	$	2.1	$	-	$	-	$	2.1

(a)

As of March 31, 2024, we had no commodity derivative assets or liabilities, or related gross collateral amounts, that were subject to master netting agreements.


	As of December 31, 2023
	Level 1		Level 2		Level 3		Cash Collateral and Counterparty Netting (a)			Total
	(in millions)
Assets:
Commodity derivatives - Gas Utilities	$	-	$	1.9	$	-	$	(1.9	)	$	-
Total	$	-	$	1.9	$	-	$	(1.9	)	$	-

Liabilities:
Commodity derivatives - Gas Utilities	$	-	$	10.1	$	-	$	(3.3	)	$	6.8
Total	$	-	$	10.1	$	-	$	(3.3	)	$	6.8

(a)

As of December 31, 2023, $1.9 million of our commodity derivative assets and $3.3 million of our commodity derivative liabilities, as well as related gross collateral amounts, were subject to master netting agreements.

Pension and Postretirement Plan Assets

Fair value measurements also apply to the valuation of our pension and postretirement plan assets. Current accounting guidance requires employers to annually disclose information about the fair value measurements of their assets of a defined benefit pension or other postretirement plan. The fair value of these assets is presented in Note 13 to the Consolidated Financial Statements included in our 2023 Annual Report on Form 10-K.

Other Fair Value Measures

The carrying amount of cash and cash equivalents, restricted cash and equivalents and short-term borrowings approximates fair value due to their liquid or short-term nature. Cash, cash equivalents and restricted cash are classified in Level 1 in the fair value hierarchy. Notes payable consist of commercial paper borrowings and are not traded on an exchange; therefore, they are classified as Level 2 in the fair value hierarchy.

The following table presents the carrying amounts and fair values of financial instruments not recorded at fair value on the Consolidated Balance Sheets (in millions) as of:


	March 31, 2024				December 31, 2023
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Long-term debt, including current maturities (a)	$	4,402.8	$	4,155.6	$	4,401.2	$	4,215.6

(a)

Long-term debt is valued based on observable inputs available either directly or indirectly for similar liabilities in active markets and therefore is classified in Level 2 in the fair value hierarchy. Carrying amount of long-term debt is net of deferred financing costs.

Selected Balance Sheet Information: Accrued Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Selected Balance Sheet Information [Abstract]
Accrued employee compensation, benefits and withholdings	$ 52.2	$ 74.8
Accrued property taxes	55.8	52.7
Customer deposits and prepayments	60.3	76.0
Accrued interest	56.0	46.3
Other (none of which is individually significant)	39.6	43.5
Total accrued liabilities	$ 263.9	$ 293.3

Employee Benefit Plans: Components of Net Periodic Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 0.6	$ 0.6
Interest cost	4.1	4.4
Expected return on plan assets	(4.5)	(4.7)
Net amortization of prior service costs	0.0	0.0
Recognized net actuarial loss (gain)	0.5	0.5
Net periodic expense (benefit)	0.7	0.8
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	1.0	0.9
Interest cost	0.3	0.4
Expected return on plan assets	0.0	0.0
Net amortization of prior service costs	0.0	0.0
Recognized net actuarial loss (gain)	0.0	0.0
Net periodic expense (benefit)	1.3	1.3
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	0.4	0.4
Interest cost	0.6	0.6
Expected return on plan assets	(0.1)	(0.1)
Net amortization of prior service costs	0.1	0.0
Recognized net actuarial loss (gain)	0.0	0.0
Net periodic expense (benefit)	$ 1.0	$ 0.9

Business Segment Information: Information Relating to Segments Statement of Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information
Revenue	$ 726.4	$ 921.2
Operating income	193.3	174.9
Capital expenditures	174.3	103.7
Corporate, Non-Segment
Segment Reporting Information
Operating income	(2.1)	(0.8)
Capital expenditures	2.4	1.1
Operating Segments \| Electric Utilities
Segment Reporting Information
Revenue	222.2	218.7
Operating income	64.6	61.1
Capital expenditures	86.9	47.8
Operating Segments \| Gas Utilities
Segment Reporting Information
Revenue	508.7	706.9
Operating income	130.8	114.6
Capital expenditures	85.0	54.8
External Revenues
Segment Reporting Information
Revenue	726.4	921.2
External Revenues \| Operating Segments \| Electric Utilities
Segment Reporting Information
Revenue	219.3	215.9
External Revenues \| Operating Segments \| Gas Utilities
Segment Reporting Information
Revenue	507.1	705.3
Inter-segment Revenues \| Corporate, Non-Segment
Segment Reporting Information
Revenue	(4.5)	(4.4)
Inter-segment Revenues \| Operating Segments \| Electric Utilities
Segment Reporting Information
Revenue	2.9	2.8
Inter-segment Revenues \| Operating Segments \| Gas Utilities
Segment Reporting Information
Revenue	$ 1.6	$ 1.6

Revenue (Tables)

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The following tables depict the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition for each of the reportable segments for the three months ended March 31, 2024 and 2023. Sales tax and other similar taxes are excluded from revenues.


Three Months Ended March 31, 2024	Electric Utilities		Gas Utilities		Inter-segment Eliminations			Total
Customer types:	(in millions)
Retail	$	188.3	$	437.4	$	-		$	625.7
Transportation		-		51.7		(0.1	)		51.6
Wholesale		8.5		-		-			8.5
Market - off-system sales		6.6		-		-			6.6
Transmission/Other		18.0		11.2		(4.4	)		24.8
Revenue from contracts with customers	$	221.4	$	500.3	$	(4.5	)	$	717.2
Other revenues		0.8		8.4		-			9.2
Total revenues	$	222.2	$	508.7	$	(4.5	)	$	726.4

Timing of revenue recognition:
Services transferred at a point in time	$	8.7	$	-	$	-		$	8.7
Services transferred over time		212.7		500.3		(4.5	)		708.5
Revenue from contracts with customers	$	221.4	$	500.3	$	(4.5	)	$	717.2


Three Months Ended March 31, 2023	Electric Utilities		Gas Utilities		Inter-segment Eliminations			Total
Customer types:	(in millions)
Retail	$	174.9	$	635.5	$	-		$	810.4
Transportation		-		52.8		(0.1	)		52.7
Wholesale		9.4		-		-			9.4
Market - off-system sales		16.1		0.3		-			16.4
Transmission/Other		17.4		10.1		(4.3	)		23.2
Revenue from contracts with customers	$	217.8	$	698.7	$	(4.4	)	$	912.1
Other revenues		0.9		8.2		-			9.1
Total revenues	$	218.7	$	706.9	$	(4.4	)	$	921.2

Timing of revenue recognition:
Services transferred at a point in time	$	8.7	$	-	$	-		$	8.7
Services transferred over time		209.1		698.7		(4.4	)		903.4
Revenue from contracts with customers	$	217.8	$	698.7	$	(4.4	)	$	912.1

Selected Balance Sheet Information: Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Selected Balance Sheet Information [Abstract]
Billed Accounts Receivable	$ 216.1	$ 198.5
Unbilled Revenue	122.2	154.0
Less: Allowance for Credit Losses	(3.9)	(2.2)	$ (5.4)	$ (3.0)
Account Receivable, net	$ 334.4	$ 350.3

Employee Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2024

Defined Benefit Plan Disclosure [Line Items]

Components of Net Periodic Benefit Cost

The components of net periodic expense were as follows (in millions):


	Defined Benefit Pension Plan						Supplemental Non-qualified Defined Benefit Plans				Non-pension Defined Benefit Postretirement Healthcare Plan
Three Months Ended March 31,	2024			2023			2024		2023		2024			2023
Service cost	$	0.6		$	0.6		$	1.0	$	0.9	$	0.4		$	0.4
Interest cost		4.1			4.4			0.3		0.4		0.6			0.6
Expected return on plan assets		(4.5	)		(4.7	)		-		-		(0.1	)		(0.1	)
Net amortization of prior service costs		-			-			-		-		0.1			-
Recognized net actuarial loss (gain)		0.5			0.5			-		-		-			-
Net periodic expense (benefit)	$	0.7		$	0.8		$	1.3	$	1.3	$	1.0		$	0.9

Schedule of Employer Contribution to Employee Benefit Plans

Contributions made in the first three months of 2024 and anticipated contributions for 2024 and 2025 are as follows (in millions):


	Contributions Made		Additional Contributions		Contributions
	Three Months Ended March 31, 2024		Anticipated for 2024		Anticipated for 2025
Defined Benefit Pension Plan	$	-	$	2.3	$	1.8
Non-pension Defined Benefit Postretirement Healthcare Plan	$	1.2	$	3.4	$	4.4
Supplemental Non-qualified Defined Benefit and Defined Contribution Plans	$	0.6	$	1.8	$	2.8

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Schedule of Fair Value Hierarchy, Measured on Recurring Basis


	As of March 31, 2024
	Level 1		Level 2		Level 3		Cash Collateral and Counterparty Netting (a)		Total
	(in millions)
Assets:
Commodity derivatives - Gas Utilities	$	-	$	-	$	-			$	-
Total	$	-	$	-	$	-	$	-	$	-

Liabilities:
Commodity derivatives - Gas Utilities	$	-	$	2.1	$	-			$	2.1
Total	$	-	$	2.1	$	-	$	-	$	2.1

(a)

As of March 31, 2024, we had no commodity derivative assets or liabilities, or related gross collateral amounts, that were subject to master netting agreements.


	As of December 31, 2023
	Level 1		Level 2		Level 3		Cash Collateral and Counterparty Netting (a)			Total
	(in millions)
Assets:
Commodity derivatives - Gas Utilities	$	-	$	1.9	$	-	$	(1.9	)	$	-
Total	$	-	$	1.9	$	-	$	(1.9	)	$	-

Liabilities:
Commodity derivatives - Gas Utilities	$	-	$	10.1	$	-	$	(3.3	)	$	6.8
Total	$	-	$	10.1	$	-	$	(3.3	)	$	6.8

(a)

Fair Value, by Balance Sheet Grouping

The following table presents the carrying amounts and fair values of financial instruments not recorded at fair value on the Consolidated Balance Sheets (in millions) as of:


	March 31, 2024				December 31, 2023
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Long-term debt, including current maturities (a)	$	4,402.8	$	4,155.6	$	4,401.2	$	4,215.6

(a)

Financing - Schedule of Short-term Debt and Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Short-Term Debt [Line Items]
Amount outstanding	$ 0.0		$ 0.0
Revolving Credit Facility \| Commercial Paper
Short-Term Debt [Line Items]
Amount outstanding	0.0		0.0
Letters of Credit	3.7		3.7
Available capacity	746.3		$ 746.3
Maximum amount outstanding (based on daily outstanding balances)	0.0	$ 548.7
Average amount outstanding (based on daily outstanding balances)	$ 0.0	$ 331.3
Weighted average interest rates		4.91%

Risk Management And Derivatives

3 Months Ended

Mar. 31, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Risk Management And Derivatives

(7)

Risk Management and Derivatives

Market and Credit Risk Disclosures

Our activities in the energy industry expose us to a number of risks in the normal operations of our businesses. Depending on the activity, we are exposed to varying degrees of market risk and credit risk.

Market Risk

Market risk is the potential loss that may occur as a result of an adverse change in market price, rate or supply. We are exposed but not limited to, the following market risks:

•

Commodity price risk associated with our retail natural gas and wholesale electric power marketing activities and our fuel procurement for several of our gas-fired generation assets, which include market fluctuations due to unpredictable factors such as weather, geopolitical events, pandemics, market speculation, recession, inflation, pipeline constraints, and other factors that may impact natural gas and electric supply and demand; and

•

Interest rate risk associated with future debt, including reduced access to liquidity during periods of extreme capital markets volatility.

Credit Risk

Credit risk is the risk of financial loss resulting from non-performance of contractual obligations by a counterparty.

We attempt to mitigate our credit exposure by conducting business primarily with high credit quality entities, setting tenor and credit limits commensurate with counterparty financial strength, obtaining master netting agreements and mitigating credit exposure with less creditworthy counterparties through parental guarantees, cash collateral requirements, letters of credit and other security agreements.

We perform periodic credit evaluations of our customers and adjust credit limits based upon payment history and the customers’ current creditworthiness, as determined by review of their current credit information. We maintain a provision for estimated credit losses based upon historical experience, changes in current market conditions, expected losses and any specific customer collection issue that is identified.

Derivatives and Hedging Activity

Our derivative and hedging activities included in the accompanying Consolidated Balance Sheets, Consolidated Statements of Income and Consolidated Statements of Comprehensive Income are detailed below and in Note 8.

The operations of our Utilities, including natural gas sold by our Gas Utilities and natural gas used by our Electric Utilities’ generation plants or those plants under PPAs where our Electric Utilities must provide the generation fuel (tolling agreements), expose our utility customers to natural gas price volatility. Therefore, as allowed or required by state utility commissions, we enter into commission approved hedging programs utilizing natural gas futures, options, over-the-counter swaps and basis swaps to reduce our customers’ underlying exposure to these fluctuations. These transactions are considered derivatives, and in accordance with accounting standards for derivatives and hedging, mark-to-market adjustments are recorded as Derivative assets or Derivative liabilities on the accompanying Consolidated Balance Sheets, net of balance sheet offsetting as permitted by GAAP.

For our regulated Utilities’ hedging plans, unrealized and realized gains and losses, as well as option premiums and commissions on these transactions, are recorded as Regulatory assets or Regulatory liabilities in the accompanying Consolidated Balance Sheets in accordance with the state regulatory commission guidelines. When the related costs are recovered through our rates, the hedging activity is recognized in the Consolidated Statements of Income.

To support our Choice Gas Program customers, we buy, sell and deliver natural gas at competitive prices by managing commodity price risk. As a result of these activities, this area of our business is exposed to risks associated with changes in the market price of natural gas. We manage our exposure to such risks using over-the-counter and exchange traded options and swaps with counterparties in anticipation of forecasted purchases and sales during time frames ranging from April 2024 through December 2025. A portion of our over-the-counter swaps have been designated as cash flow hedges to mitigate the commodity price risk associated with deliveries under fixed price forward contracts to deliver gas to our Choice Gas Program customers. The gain or loss on these designated derivatives is reported in AOCI in the accompanying Consolidated Balance Sheets and reclassified into earnings in the same period that the underlying hedged item is recognized in earnings. Effectiveness of our hedging position is evaluated at least quarterly.

The contract or notional amounts and terms of the electric and natural gas derivative commodity instruments held at our Utilities are composed of both long and short positions. We had the following net long and (short) positions as of:


	March 31, 2024					December 31, 2023
	Notional Amounts (MMBtus)			Maximum Term (months) (a)		Notional Amounts (MMBtus)		Maximum Term (months) (a)
Natural gas futures purchased		-		N/A			650,000		3
Natural gas options purchased, net		-		N/A			2,850,000		3
Natural gas basis swaps purchased		-		N/A			1,050,000		3
Natural gas over-the-counter swaps, net (b)		2,600,000			20		3,890,000		21
Natural gas physical contracts, net (c)		(444,110	)		7		12,582,415		10

(a)

Term reflects the maximum forward period hedged.

(b)

As of March 31, 2024, 695,000 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges.

(c)

Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.

We have certain derivative contracts which contain credit provisions. These credit provisions may require the Company to post collateral when credit exposure to the Company is in excess of a negotiated line of unsecured credit. At March 31, 2024, the Company posted $0.1 million related to such provisions, which is included in Other current assets on the Consolidated Balance Sheets.

Derivatives by Balance Sheet Classification

The following table presents the fair value and balance sheet classification of our derivative instruments (in millions) as of:


	Balance Sheet Location	March 31, 2024			December 31, 2023
Derivatives designated as hedges:
Liability derivative instruments:
Current commodity derivatives	Derivative liabilities, current	$	(0.7	)	$	(2.7	)
Noncurrent commodity derivatives	Other assets, non-current		(0.1	)		(0.2	)
Total derivatives designated as hedges		$	(0.8	)	$	(2.9	)

Derivatives not designated as hedges:
Liability derivative instruments:
Current commodity derivatives	Derivative liabilities, current	$	(1.3	)	$	(3.8	)
Noncurrent commodity derivatives	Other deferred credits and other liabilities		-			(0.1	)
Total derivatives not designated as hedges		$	(1.3	)	$	(3.9	)

Derivatives Designated as Hedge Instruments

The impact of cash flow hedges on our Consolidated Statements of Comprehensive Income and Consolidated Statements of Income are presented below for the three months ended March 31, 2024 and 2023. Note that this presentation does not reflect the gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled.


	Three Months Ended March 31,					Three Months Ended March 31,
	2024		2023			2024			2023
Derivatives in Cash Flow Hedging Relationships	Amount of Gain/(Loss) Recognized in OCI				Income Statement Location	Amount of Gain/(Loss) Reclassified from AOCI into Income
	(in millions)					(in millions)
Interest rate swaps	$	0.7	$	0.7	Interest expense	$	(0.7	)	$	(0.7	)
Commodity derivatives		2.4		0.8	Fuel, purchased power and cost of natural gas sold		(2.6	)		(2.0	)
Total	$	3.1	$	1.5		$	(3.3	)	$	(2.7	)

As of March 31, 2024, $3.6 million of net losses related to our interest rate swaps and commodity derivatives are expected to be reclassified from AOCI into earnings within the next 12 months. As market prices fluctuate, estimated and actual realized gains or losses will change during future periods.

Derivatives Not Designated as Hedge Instruments

The following table summarizes the impacts of derivative instruments not designated as hedge instruments on our Consolidated Statements of Income for the three months ended March 31, 2024 and 2023. Note that this presentation does not reflect the expected gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled.


		Three Months Ended March 31,
		2024		2023
Derivatives Not Designated as Hedging Instruments	Location of Gain/(Loss) on Derivatives Recognized in Income	Amount of Gain/(Loss) on Derivatives Recognized in Income
		(in millions)
Commodity derivatives	Fuel, purchased power and cost of natural gas sold	$	0.6	$	(3.1	)
		$	0.6	$	(3.1	)

As discussed above, financial instruments used in our regulated Gas Utilities are not designated as cash flow hedges. However, there is no earnings impact because the unrealized gains and losses arising from the use of these financial instruments are recorded as Regulatory assets or Regulatory liabilities. We did not have any net unrealized losses included in our Regulatory asset accounts related to these financial instruments in our Gas Utilities as of March 31, 2024 and the amount was $5.1 million as of December 31, 2023.

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest Rate Swap
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification,Tax (Benefit)	$ (0.1)	$ (0.2)
Commodity Contract
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification,Tax (Benefit)	(0.6)	(0.5)
(Tax) benefit on net unrealized gains (losses) on commodity derivatives	$ 0.0	$ 0.3

Financing: Debt Covenants (Additional Information) (Details)	Mar. 31, 2024
Line of Credit Facility [Line Items]
Consolidated indebtedness to capitalization ratio	0.57
Maximum
Line of Credit Facility [Line Items]
Consolidated indebtedness to capitalization ratio	0.65
Wyoming Electric
Line of Credit Facility [Line Items]
Consolidated indebtedness to capitalization ratio	0.52
Wyoming Electric \| Maximum
Line of Credit Facility [Line Items]
Consolidated indebtedness to capitalization ratio	0.6

Other Comprehensive Income: Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	$ 46.0	$ 44.1
Fuel, purchased power and cost of natural gas sold	316.6	526.3
Income tax expense	(16.9)	(14.7)
Net income	131.6	117.4
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net income	(2.6)	(2.1)
Cash Flow Hedging \| Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income taxes	(3.3)	(2.7)
Income tax expense	0.7	0.6
Net income	(2.6)	(2.1)
Cash Flow Hedging \| Reclassification out of Accumulated Other Comprehensive Income \| Interest Rate Swap
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	(0.7)	(0.7)
Cash Flow Hedging \| Reclassification out of Accumulated Other Comprehensive Income \| Commodity Contract
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Fuel, purchased power and cost of natural gas sold	$ (2.6)	$ (2.0)

Revenue

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Revenue

(4)

Revenue


Three Months Ended March 31, 2024	Electric Utilities		Gas Utilities		Inter-segment Eliminations			Total
Customer types:	(in millions)
Retail	$	188.3	$	437.4	$	-		$	625.7
Transportation		-		51.7		(0.1	)		51.6
Wholesale		8.5		-		-			8.5
Market - off-system sales		6.6		-		-			6.6
Transmission/Other		18.0		11.2		(4.4	)		24.8
Revenue from contracts with customers	$	221.4	$	500.3	$	(4.5	)	$	717.2
Other revenues		0.8		8.4		-			9.2
Total revenues	$	222.2	$	508.7	$	(4.5	)	$	726.4

Timing of revenue recognition:
Services transferred at a point in time	$	8.7	$	-	$	-		$	8.7
Services transferred over time		212.7		500.3		(4.5	)		708.5
Revenue from contracts with customers	$	221.4	$	500.3	$	(4.5	)	$	717.2


Three Months Ended March 31, 2023	Electric Utilities		Gas Utilities		Inter-segment Eliminations			Total
Customer types:	(in millions)
Retail	$	174.9	$	635.5	$	-		$	810.4
Transportation		-		52.8		(0.1	)		52.7
Wholesale		9.4		-		-			9.4
Market - off-system sales		16.1		0.3		-			16.4
Transmission/Other		17.4		10.1		(4.3	)		23.2
Revenue from contracts with customers	$	217.8	$	698.7	$	(4.4	)	$	912.1
Other revenues		0.9		8.2		-			9.1
Total revenues	$	218.7	$	706.9	$	(4.4	)	$	921.2

Timing of revenue recognition:
Services transferred at a point in time	$	8.7	$	-	$	-		$	8.7
Services transferred over time		209.1		698.7		(4.4	)		903.4
Revenue from contracts with customers	$	217.8	$	698.7	$	(4.4	)	$	912.1

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Regulatory Matters: Regulatory Matters (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Regulatory assets	$ 431,100,000	$ 480,100,000
Regulatory assets, current	(147,300,000)	(175,700,000)
Regulatory assets, non-current	283,800,000	304,400,000
Regulatory liabilities	553,400,000	566,600,000
Regulatory liabilities, current	(89,900,000)	(98,900,000)
Regulatory liabilities, non-current	463,500,000	467,700,000
Deferred energy and gas costs
Regulatory liabilities	85,700,000	88,900,000
Employee benefit plan costs and related deferred taxes
Regulatory liabilities	35,700,000	36,200,000
Cost of removal
Regulatory liabilities	182,200,000	181,900,000
Excess deferred income taxes
Regulatory liabilities	243,200,000	247,100,000
Other regulatory liabilities
Regulatory liabilities	6,600,000	12,500,000
Storm Costs
Regulatory assets	144,900,000	199,600,000
Deferred energy and gas costs
Regulatory assets	57,500,000	55,100,000
Deferred gas cost adjustments
Regulatory assets	8,100,000	4,100,000
Gas price derivatives
Regulatory assets	0	5,100,000
Deferred taxes on AFUDC
Regulatory assets	7,400,000	7,100,000
Employee benefit plans and related deferred taxes
Regulatory assets	88,200,000	89,300,000
Environmental
Regulatory assets	5,900,000	2,900,000
Loss on reacquired debt
Regulatory assets	17,000,000	17,400,000
Deferred taxes on flow through accounting
Regulatory assets	80,500,000	74,700,000
Decommissioning costs
Regulatory assets	2,400,000	2,400,000
Other regulatory assets
Regulatory assets	$ 19,200,000	$ 22,400,000

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating activities:
Net income	$ 131.6	$ 117.4
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	65.9	61.6
Deferred financing cost amortization	2.7	2.4
Stock compensation	2.4	1.8
Deferred income taxes	16.7	14.9
Employee benefit plans	3.0	3.0
Other adjustments, net	(0.3)	(2.9)
Change in certain operating assets and liabilities:
Materials, supplies and fuel	30.4	76.1
Accounts receivable and other current assets	(11.3)	28.7
Accounts payable and other current liabilities	(59.6)	(127.2)
Regulatory assets	54.8	154.7
Other operating activities, net	(2.9)	(1.8)
Net cash provided by operating activities	233.4	328.7
Investing activities:
Property, plant and equipment additions	(176.2)	(119.1)
Other investing activities	(0.7)	17.6
Net cash (used in) investing activities	(176.9)	(101.5)
Financing activities:
Dividends paid on common stock	(44.4)	(41.4)
Common stock issued	31.2	27.4
Net borrowings (payments) of Revolving Credit Facility and CP Program	0.0	(535.6)
Long-term debt - issuance	0.0	350.0
Distributions to non-controlling interests	(5.6)	(4.5)
Other financing activities	(1.0)	(5.0)
Net cash (used in) financing activities	(19.8)	(209.1)
Net change in cash, restricted cash and cash equivalents	36.7	18.1
Cash, restricted cash and cash equivalents beginning of period	93.0	27.0
Cash, restricted cash and cash equivalents end of period	129.7	45.1
Supplemental cash flow information:
Interest (net of amounts capitalized)	(33.6)	(27.6)
Accrued property, plant and equipment purchases at March 31,	$ 37.7	$ 42.1

Risk Management and Derivatives: Derivatives by Balance Sheet Classification (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ (0.8)	$ (2.9)
Commodity Contract \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(1.3)	(3.9)
Other assets, non-current \| Commodity Contract \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(0.1)	(0.2)
Derivative liabilities, current \| Commodity Contract \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(0.7)	(2.7)
Derivative liabilities, current \| Commodity Contract \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(1.3)	(3.8)
Other deferred credits and other liabilities \| Commodity Contract \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0.0	$ (0.1)

Income Taxes

3 Months Ended

Mar. 31, 2024

Income Tax Disclosure [Abstract]

Income Taxes

(11)

Income Taxes

IRS Revenue Procedure 2023-15

On April 14, 2023, the IRS released Revenue Procedure 2023-15 “Amounts paid to improve tangible property.” The Revenue Procedure provides a safe harbor method of accounting that taxpayers may use to determine whether costs to repair, maintain, replace, or improve natural gas transmission and distribution property must be capitalized. The revenue procedure may be adopted in tax years ending after May 1, 2023. We are currently assessing the Revenue Procedure to determine its impact on our tax repairs deduction.

Income Tax Benefit (Expense) and Effective Tax Rates

Three Months Ended March 31, 2024 Compared to the Three Months Ended March 31, 2023

Income tax (expense) for the three months ended March 31, 2024 was $16.9 million compared to $14.7 million reported for the same period in 2023. For the three months ended March 31, 2024, the effective tax rate was 11.4% which was comparable to 11.1% for the same period in 2023.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Schedule of Earnings Per Share Reconciliation

A reconciliation of share amounts used to compute earnings per share in the accompanying Consolidated Statements of Income was as follows (in millions, except per share amounts):


	Three Months Ended March 31,
	2024		2023
Net income available for common stock	$	127.9	$	114.1

Weighted average shares - basic		68.2		66.0
Dilutive effect of equity compensation		0.1		0.1
Weighted average shares - diluted		68.3		66.1

Net income available for common stock, per share - Diluted	$	1.87	$	1.73

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following securities were excluded from the diluted earnings per share computation because of their anti-dilutive nature (in millions of shares):

Other Comprehensive Income

3 Months Ended

Mar. 31, 2024

Statement of Comprehensive Income [Abstract]

Other Comprehensive Income

(9)

Other Comprehensive Income

We record deferred gains (losses) in AOCI related to interest rate swaps designated as cash flow hedges, commodity contracts designated as cash flow hedges and the amortization of components of our defined benefit plans. Deferred gains (losses) for our commodity contracts designated as cash flow hedges are recognized in earnings upon settlement, while deferred gains (losses) related to our interest rate swaps are recognized in earnings as they are amortized.

The following table details reclassifications out of AOCI and into Net income. The amounts in parentheses below indicate decreases to Net income in the Consolidated Statements of Income for the period, net of tax (in millions):


		Amount Reclassified from AOCI
	Location on the Consolidated Statements of Income	Three Months Ended March 31,
		2024			2023
Gains and (losses) on cash flow hedges:
Interest rate swaps	Interest expense	$	(0.7	)	$	(0.7	)
Commodity contracts	Fuel, purchased power and cost of natural gas sold		(2.6	)		(2.0	)
		$	(3.3	)	$	(2.7	)
Income tax	Income tax expense		0.7			0.6
Total reclassification adjustments related to cash flow hedges, net of tax		$	(2.6	)	$	(2.1	)
Total reclassifications		$	(2.6	)	$	(2.1	)

Balances by classification included within AOCI, net of tax on the accompanying Consolidated Balance Sheets were as follows (in millions):


	Derivatives Designated as Cash Flow Hedges
	Interest Rate Swaps			Commodity Derivatives			Employee Benefit Plans			Total
As of December 31, 2023	$	(6.1	)	$	(2.5	)	$	(6.2	)	$	(14.8	)
Other comprehensive income (loss)
before reclassifications		-			(0.1	)		-			(0.1	)
Amounts reclassified from AOCI		0.6			2.0			-			2.6
As of March 31, 2024	$	(5.5	)	$	(0.6	)	$	(6.2	)	$	(12.3	)


	Derivatives Designated as Cash Flow Hedges
	Interest Rate Swaps			Commodity Derivatives			Employee Benefit Plans			Total
As of December 31, 2022	$	(8.3	)	$	(1.2	)	$	(6.1	)	$	(15.6	)
Other comprehensive income (loss)
before reclassifications		-			(0.9	)		-			(0.9	)
Amounts reclassified from AOCI		0.6			1.5			-			2.1
As of March 31, 2023	$	(7.7	)	$	(0.6	)	$	(6.1	)	$	(14.4	)

Consolidated Statements of Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Stockholders' Equity [Abstract]
Dividends on common stock (usd per share)	$ 0.65	$ 0.625

Financing

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Financing

(5)

Financing

Short-term Debt

Revolving Credit Facility and CP Program

Our Revolving Credit Facility and CP Program, which are classified as Notes payable on the Consolidated Balance Sheets, had the following borrowings, outstanding letters of credit, and available capacity (dollars in millions) as of:


	March 31, 2024		December 31, 2023
Amount outstanding	$	-	$	-
Letters of credit (a)	$	3.7	$	3.7
Available capacity	$	746.3	$	746.3
Weighted average interest rates	N/A		N/A

(a)

Letters of credit are off-balance sheet commitments that reduce the borrowing capacity available on our corporate Revolving Credit Facility.

Revolving Credit Facility and CP Program borrowing activity was as follows (dollars in millions):


	Three Months Ended March 31,
	2024		2023
Maximum amount outstanding (based on daily outstanding balances)	$	-	$	548.7
Average amount outstanding (based on daily outstanding balances)	$	-	$	331.3
Weighted average interest rates	N/A			4.91	%

Financial Covenants

Revolving Credit Facility

We were in compliance with all of our Revolving Credit Facility covenants as of March 31, 2024. We are required to maintain a Consolidated Indebtedness to Capitalization Ratio not to exceed 0.65 to 1.00. Subject to applicable cure periods, a violation of this covenant would constitute an event of default that entitles the lenders to terminate their remaining commitments and accelerate all principal and interest outstanding. As of March 31, 2024, our Consolidated Indebtedness to Capitalization Ratio was 0.57 to 1.00.

Wyoming Electric

Wyoming Electric was in compliance with all covenants within its financing agreements as of March 31, 2024. Wyoming Electric is required to maintain a debt to capitalization ratio of no more than 0.60 to 1.00. As of March 31, 2024, Wyoming Electric's debt to capitalization ratio was 0.52 to 1.00.

Equity

At-the-Market Equity Offering Program

ATM activity was as follows (in millions, except Average price per share amounts):


	Three Months Ended March 31,
	2024		2023
August 4, 2020 ATM Program
Proceeds, (net of issuance costs of $0.0 and $(0.3), respectively)	$	-	$	27.4
Number of shares issued		-		0.4

June 16, 2023 ATM Program
Proceeds, (net of issuance costs of $(0.3) and $0.0, respectively)	$	31.2	$	-
Number of shares issued		0.6		-

Total activity under both ATM Programs
Proceeds, (net of issuance costs of $(0.3) and $(0.3), respectively)	$	31.2	$	27.4
Number of shares issued		0.6		0.4
Average price per share	$	52.51	$	62.21

As of March 31, 2024, there were 47,596 shares issued under the ATM Program, but not settled.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Business Segment Information

3 Months Ended

Mar. 31, 2024

Segment Reporting Information, Additional Information [Abstract]

Business Segment Information

(12)

Business Segment Information

Our Chief Executive Officer, who is considered to be our CODM, reviews financial information presented on an operating segment basis for purposes of making decisions, allocating resources and assessing financial performance. Our CODM assesses the performance of our operating segments based on operating income. Our CODM reviews capital expenditures by operating segment rather than any individual or total asset amount.

We conduct our business operations through two operating segments: Electric Utilities and Gas Utilities. Certain unallocated corporate expenses that support our operating segments are presented as Corporate and Other. Corporate and Other also includes business development activities that are not part of our operating segments and inter-segment eliminations. Our operating segments are equivalent to our reportable segments.

Segment information was as follows (in millions):


	Electric Utilities		Gas Utilities		Corporate and Other			Total
Three Months Ended March 31, 2024
External revenues	$	219.3	$	507.1	$	-		$	726.4
Inter-segment revenues		2.9		1.6		(4.5	)		-
Operating income		64.6		130.8		(2.1	)		193.3
Capital expenditures (a)		86.9		85.0		2.4			174.3
Three Months Ended March 31, 2023
External revenues	$	215.9	$	705.3	$	-		$	921.2
Inter-segment revenues		2.8		1.6		(4.4	)		-
Operating income		61.1		114.6		(0.8	)		174.9
Capital expenditures (a)		47.8		54.8		1.1			103.7

(a)

Includes accruals for property, plant and equipment as disclosed in supplemental cash flow information in the Consolidated Statements of Cash Flows in the Consolidated Financial Statements.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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-Section 50
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+ Details

Employee Benefit Plans: Plan Contributions (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	$ 1.8
Payment for Pension Benefits	0.0
Estimated Future Employer Contributions in Current Fiscal Year	2.3
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	4.4
Payment for Pension Benefits	1.2
Estimated Future Employer Contributions in Current Fiscal Year	3.4
Supplemental Non-Qualified Defined Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	2.8
Payment for Pension Benefits	0.6
Estimated Future Employer Contributions in Current Fiscal Year	$ 1.8

Management's Statement

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Management's Statement

(1)

Management’s Statement

The unaudited Consolidated Financial Statements included herein have been prepared by Black Hills Corporation (together with our subsidiaries the “Company”, “us”, “we” or “our”), pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to such rules and regulations; however, we believe that the footnotes adequately disclose the information presented. These Consolidated Financial Statements should be read in conjunction with the consolidated financial statements and the notes included in our 2023 Annual Report on Form 10-K.

Use of Estimates and Basis of Presentation

The information furnished in the accompanying Consolidated Financial Statements reflects certain estimates required and all adjustments, including accruals, which are, in the opinion of management, necessary for a fair presentation of the March 31, 2024, December 31, 2023 and March 31, 2023 financial information. Certain lines of business in which we operate are highly seasonal, and our interim results of operations are not necessarily indicative of the results of operations to be expected for an entire year.

Recently Issued Accounting Standards

Improvements to Reportable Segment Disclosures, ASU 2023-07

In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures, which expands public entities’ segment disclosures by requiring disclosure of significant segment expenses that are regularly reviewed by the CODM and included within each reported measure of segment profit or loss, an amount and description of its composition for other segment items, and interim disclosures of a reportable segment’s profit or loss and assets. The ASU also allows, in addition to the measure that is most consistent with GAAP, the disclosure of additional measures of segment profit or loss that are used by the CODM in assessing segment performance and deciding how to allocate resources. The ASU is effective for our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, and subsequent interim periods, with early adoption permitted. We do not expect the ASU to have an impact on our financial position, results of operations and cash flows; however, are currently evaluating the impact on our consolidated financial statement disclosures.

Improvements to Income Tax Disclosures, ASU 2023-09

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures, which expands public entities’ annual disclosures by requiring disclosure of tax rate reconciliation amounts and percentages for specific categories, income taxes paid disaggregated by federal and state taxes, and income tax expense disaggregated by federal and state taxes jurisdiction. The ASU is effective for our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, with early adoption permitted. We do not expect the ASU to have an impact on our financial position, results of operations and cash flows; however, are currently evaluating the impact on our consolidated financial statement disclosures.

Earnings Per Share - Earnings Per Share Reconciliation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net Income (Loss)	$ 127.9	$ 114.1
Weighted average shares - Basic (in shares)	68.2	66.0
Dilutive effect of equity compensation	0.1	0.1
Weighted average shares - diluted (in shares)	68.3	66.1
Net income available for common stock, per share - Diluted	$ 1.87	$ 1.73

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 34: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-7

Reference 35: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A

Reference 37: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B

Reference 38: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 39: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Line Items]
Income tax (expense)	$ 16.9	$ 14.7
Effective Tax Rate	11.40%	11.10%

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Regulatory Matters: Gas Utilities Regulatory Activity (Details) $ in Millions	May 01, 2024 USD ($) mi	Mar. 26, 2024 USD ($)	Jan. 17, 2024 USD ($)	Dec. 04, 2023 USD ($) mi	May 18, 2023 mi	May 09, 2023 mi
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Gas \| Rate Review Filed with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments \| mi						10,000
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Gas \| Settlement Reached with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage		51.00%
Public Utilities, Approved Debt Capital Structure, Percentage		49.00%
Public Utilities, Approved Return on Equity, Percentage		9.30%
Public Utilities, Approved Rate Increase (Decrease), Amount \| $		$ 20.2
Iowa Utilities Board (IUB) \| Black Hills Energy - Iowa Gas \| Rate Review Filed with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments \| mi	5,000
Public Utilities, Requested Rate Increase (Decrease), Amount \| $	$ 20.7
Public utilities, requested equity capital structure, percentage	51.00%
Public utilities, requested debt capital structure, percentage	49.00%
Public Utilities, Requested Return on Equity, Percentage	10.50%
Arkansas Public Service Commission \| Black Hills Energy - Arkansas Gas \| Rate Review Filed with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments \| mi				7,200
Public Utilities, Requested Rate Increase (Decrease), Amount \| $				$ 44.1
Arkansas Public Service Commission \| Black Hills Energy - Arkansas Gas \| Settlement agreement reached with APSC Staff and various intervenors
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage				48.00%
Public Utilities, Approved Debt Capital Structure, Percentage				52.00%
Public Utilities, Requested Return on Equity, Percentage				10.50%
Wyoming Public Service Commission \| Black Hills Energy - Wyoming Gas \| WPSC Approved a Settlement Agreement for a General Rate Increase
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments \| mi					6,400
Public Utilities, Approved Equity Capital Structure, Percentage			51.00%
Public Utilities, Approved Debt Capital Structure, Percentage			49.00%
Public Utilities, Approved Return on Equity, Percentage			9.90%
Public Utilities, Approved Rate Increase (Decrease), Amount \| $			$ 13.9
Extension period as per settlement agreement			4 years

Risk Management and Derivatives: Utilities (Details)
$ in Millions

Mar. 31, 2024

USD ($)

MMBTU

Dec. 31, 2023

MMBTU

Derivative [Line Items]

Credit Risk Derivative Liabilities, at Fair Value | $

$ 0.1

Natural Gas, Distribution | Cash Flow Hedging

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

695,000

Natural Gas, Distribution | Natural gas futures purchased

Derivative [Line Items]

Derivative, Remaining Maturity

^[1]

3 months

Natural Gas, Distribution | Natural gas futures purchased | Long

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

650,000

Natural Gas, Distribution | Natural gas options purchased, net

Derivative [Line Items]

Derivative, Remaining Maturity

^[1]

3 months

Natural Gas, Distribution | Natural gas options purchased, net | Long

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

2,850,000

Natural Gas, Distribution | Natural gas basis swaps purchased

Derivative [Line Items]

Derivative, Remaining Maturity

^[1]

3 months

Natural Gas, Distribution | Natural gas basis swaps purchased | Long

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

1,050,000

Natural Gas, Distribution | Natural gas over-the-counter swaps, net

Derivative [Line Items]

Derivative, Remaining Maturity

^[1],[2]

20 months

21 months

Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

^[2]

2,600,000

3,890,000

Natural Gas, Distribution | Natural gas physical contracts, net

Derivative [Line Items]

Derivative, Remaining Maturity

^[1],[3]

7 months

10 months

Natural Gas, Distribution | Natural gas physical contracts, net | Long

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

^[3]

12,582,415

Natural Gas, Distribution | Natural gas physical contracts, net | Short

Derivative [Line Items]

Derivative, Nonmonetary Notional Amount

^[3]

444,110

[1]	Term reflects the maximum forward period hedged.
[2]	As of March 31, 2024, 695,000 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges.
[3]	Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.

Financing (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of Short-term Debt


	March 31, 2024		December 31, 2023
Amount outstanding	$	-	$	-
Letters of credit (a)	$	3.7	$	3.7
Available capacity	$	746.3	$	746.3
Weighted average interest rates	N/A		N/A

(a)

Letters of credit are off-balance sheet commitments that reduce the borrowing capacity available on our corporate Revolving Credit Facility.

Revolving Credit Facility and CP Program borrowing activity was as follows (dollars in millions):


	Three Months Ended March 31,
	2024		2023
Maximum amount outstanding (based on daily outstanding balances)	$	-	$	548.7
Average amount outstanding (based on daily outstanding balances)	$	-	$	331.3
Weighted average interest rates	N/A			4.91	%

Summary of ATM Activity

ATM activity was as follows (in millions, except Average price per share amounts):


	Three Months Ended March 31,
	2024		2023
August 4, 2020 ATM Program
Proceeds, (net of issuance costs of $0.0 and $(0.3), respectively)	$	-	$	27.4
Number of shares issued		-		0.4

June 16, 2023 ATM Program
Proceeds, (net of issuance costs of $(0.3) and $0.0, respectively)	$	31.2	$	-
Number of shares issued		0.6		-

Total activity under both ATM Programs
Proceeds, (net of issuance costs of $(0.3) and $(0.3), respectively)	$	31.2	$	27.4
Number of shares issued		0.6		0.4
Average price per share	$	52.51	$	62.21

As of March 31, 2024, there were 47,596 shares issued under the ATM Program, but not settled.

Selected Balance Sheet Information

3 Months Ended

Mar. 31, 2024

Selected Balance Sheet Information [Abstract]

Selected Balance Sheet Information

(13)

Selected Balance Sheet Information

Accounts Receivable and Allowance for Credit Losses

Following is a summary of Accounts receivable, net included in the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024			December 31, 2023
Billed Accounts Receivable	$	216.1		$	198.5
Unbilled Revenue		122.2			154.0
Less: Allowance for Credit Losses		(3.9	)		(2.2	)
Account Receivable, net	$	334.4		$	350.3

Changes to allowance for credit losses for the three months ended March 31, 2024 and 2023, respectively, were as follows (in millions):


	Balance at Beginning of Year		Additions Charged to Costs and Expenses		Recoveries and Other Additions		Write-offs and Other Deductions			Balance at March 31,
2024	$	2.2	$	2.0	$	1.1	$	(1.4	)	$	3.9
2023	$	3.0	$	3.7	$	0.6	$	(1.9	)	$	5.4

Materials, Supplies and Fuel

The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024		December 31, 2023
Materials and supplies	$	107.4	$	105.9
Fuel - Electric Utilities		7.5		7.7
Natural gas in storage		15.7		47.3
Total materials, supplies and fuel	$	130.6	$	160.9

Accrued Liabilities

The following amounts by major classification are included in Accrued liabilities on the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024		December 31, 2023
Accrued employee compensation, benefits and withholdings	$	52.2	$	74.8
Accrued property taxes		55.8		52.7
Customer deposits and prepayments		60.3		76.0
Accrued interest		56.0		46.3
Other (none of which is individually significant)		39.6		43.5
Total accrued liabilities	$	263.9	$	293.3

Employee Benefits Plans

3 Months Ended

Mar. 31, 2024

Retirement Benefits [Abstract]

Employee Benefit Plans

(10)

Employee Benefit Plans

Components of Net Periodic Expense

The components of net periodic expense were as follows (in millions):


	Defined Benefit Pension Plan						Supplemental Non-qualified Defined Benefit Plans				Non-pension Defined Benefit Postretirement Healthcare Plan
Three Months Ended March 31,	2024			2023			2024		2023		2024			2023
Service cost	$	0.6		$	0.6		$	1.0	$	0.9	$	0.4		$	0.4
Interest cost		4.1			4.4			0.3		0.4		0.6			0.6
Expected return on plan assets		(4.5	)		(4.7	)		-		-		(0.1	)		(0.1	)
Net amortization of prior service costs		-			-			-		-		0.1			-
Recognized net actuarial loss (gain)		0.5			0.5			-		-		-			-
Net periodic expense (benefit)	$	0.7		$	0.8		$	1.3	$	1.3	$	1.0		$	0.9

Plan Contributions

Contributions to the Defined Benefit Pension Plan are cash contributions made directly to the Pension Plan Trust account. Contributions to the Postretirement Healthcare and Supplemental Plans are primarily made in the form of benefit payments. Contributions made in the first three months of 2024 and anticipated contributions for 2024 and 2025 are as follows (in millions):


	Contributions Made		Additional Contributions		Contributions
	Three Months Ended March 31, 2024		Anticipated for 2024		Anticipated for 2025
Defined Benefit Pension Plan	$	-	$	2.3	$	1.8
Non-pension Defined Benefit Postretirement Healthcare Plan	$	1.2	$	3.4	$	4.4
Supplemental Non-qualified Defined Benefit and Defined Contribution Plans	$	0.6	$	1.8	$	2.8

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Regulatory Matters

3 Months Ended

Mar. 31, 2024

Regulated Operations [Abstract]

Regulatory Matters

(2)

Regulatory Matters

We had the following regulatory assets and liabilities (in millions):


	As of			As of
	March 31, 2024			December 31, 2023
Regulatory assets
Winter Storm Uri	$	144.9		$	199.6
Deferred energy and fuel cost adjustments		57.5			55.1
Deferred gas cost adjustments		8.1			4.1
Gas price derivatives		-			5.1
Deferred taxes on AFUDC		7.4			7.1
Employee benefit plans and related deferred taxes		88.2			89.3
Environmental		5.9			2.9
Loss on reacquired debt		17.0			17.4
Deferred taxes on flow through accounting		80.5			74.7
Decommissioning costs		2.4			2.4
Other regulatory assets		19.2			22.4
Total regulatory assets		431.1			480.1
Less current regulatory assets		(147.3	)		(175.7	)
Regulatory assets, non-current	$	283.8		$	304.4

Regulatory liabilities
Deferred energy and gas costs	$	85.7		$	88.9
Employee benefit plan costs and related deferred taxes		35.7			36.2
Cost of removal		182.2			181.9
Excess deferred income taxes		243.2			247.1
Other regulatory liabilities		6.6			12.5
Total regulatory liabilities		553.4			566.6
Less current regulatory liabilities		(89.9	)		(98.9	)
Regulatory liabilities, non-current	$	463.5		$	467.7

Regulatory Activity

Arkansas Gas

On December 4, 2023, Arkansas Gas filed a rate review with the APSC seeking recovery of significant infrastructure investments in its 7,200-mile natural gas pipeline system. The rate review requests $44.1 million in new annual revenue with a capital structure of 48% equity and 52% debt and a return on equity of 10.5%. The request seeks to finalize rates in the fourth quarter of 2024.

Colorado Gas

On May 9, 2023, Colorado Gas filed a rate review with the CPUC seeking recovery of significant infrastructure investments in its 10,000-mile natural gas pipeline system. In March 2024, Colorado Gas received final approval for a settlement agreement for a general rate increase which is expected to generate $20.2 million of new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 9.3%. Final rates were enacted on May 1, 2024, and replaced interim rates effective February 13, 2024.

Iowa Gas

On May 1, 2024, Iowa Gas filed a rate review with the IUB seeking recovery of significant infrastructure investments in its 5,000-mile natural gas pipeline system. The rate review requests $20.7 million in new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 10.5%. Iowa statute allows implementation of interim rates 10 days after filing a rate review and Iowa Gas plans to implement interim rates, subject to adjustment or refund, effective in May, 2024. The request seeks to finalize rates in the first quarter of 2025.

Wyoming Gas

On May 18, 2023, Wyoming Gas filed a rate review with the WPSC seeking recovery of significant infrastructure investments in its 6,400-mile natural gas pipeline system. On January 17, 2024, the WPSC approved a settlement agreement for a general rate increase which is expected to generate $13.9 million in new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 9.9%. New rates were effective February 1, 2024. The agreement also included approval of a four-year extension of the Wyoming Integrity Rider.

Financing: At-the-Market Equity Offering Program (Additional Information) (Details)	Mar. 31, 2024 shares
At The Market Equity Offering Program
Line of Credit Facility [Line Items]
Number of shares issued	47,596

Other Comprehensive Income (Tables)

3 Months Ended

Mar. 31, 2024

Statement of Comprehensive Income [Abstract]

Reclassification out of Accumulated Other Comprehensive Income


		Amount Reclassified from AOCI
	Location on the Consolidated Statements of Income	Three Months Ended March 31,
		2024			2023
Gains and (losses) on cash flow hedges:
Interest rate swaps	Interest expense	$	(0.7	)	$	(0.7	)
Commodity contracts	Fuel, purchased power and cost of natural gas sold		(2.6	)		(2.0	)
		$	(3.3	)	$	(2.7	)
Income tax	Income tax expense		0.7			0.6
Total reclassification adjustments related to cash flow hedges, net of tax		$	(2.6	)	$	(2.1	)
Total reclassifications		$	(2.6	)	$	(2.1	)

Schedule of Accumulated Other Comprehensive Income (Loss)

Balances by classification included within AOCI, net of tax on the accompanying Consolidated Balance Sheets were as follows (in millions):


	Derivatives Designated as Cash Flow Hedges
	Interest Rate Swaps			Commodity Derivatives			Employee Benefit Plans			Total
As of December 31, 2023	$	(6.1	)	$	(2.5	)	$	(6.2	)	$	(14.8	)
Other comprehensive income (loss)
before reclassifications		-			(0.1	)		-			(0.1	)
Amounts reclassified from AOCI		0.6			2.0			-			2.6
As of March 31, 2024	$	(5.5	)	$	(0.6	)	$	(6.2	)	$	(12.3	)


	Derivatives Designated as Cash Flow Hedges
	Interest Rate Swaps			Commodity Derivatives			Employee Benefit Plans			Total
As of December 31, 2022	$	(8.3	)	$	(1.2	)	$	(6.1	)	$	(15.6	)
Other comprehensive income (loss)
before reclassifications		-			(0.9	)		-			(0.9	)
Amounts reclassified from AOCI		0.6			1.5			-			2.1
As of March 31, 2023	$	(7.7	)	$	(0.6	)	$	(6.1	)	$	(14.4	)

Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2022		66,140,396	36,726
Beginning balance at Dec. 31, 2022	$ 3,089.9	$ 66.1	$ (2.4)	$ 1,882.7	$ 1,064.1	$ (15.6)	$ 95.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	117.4				114.1		3.3
Other comprehensive income, net of tax	1.2					1.2
Dividends on common stock	(41.4)				(41.4)
Share-based compensation (in shares)		84,735	4,388
Share-based compensation	1.7	$ 0.1	$ (0.3)	1.9
Issuance of common stock (in shares)		445,578
Issuance of common stock	27.7	$ 0.5		27.2
Issuance costs	(0.3)			(0.3)
Distributions to non-controlling interest	(4.5)						(4.5)
Ending balance (in shares) at Mar. 31, 2023		66,670,709	41,114
Ending balance at Mar. 31, 2023	3,191.7	$ 66.7	$ (2.7)	1,911.5	1,136.8	(14.4)	93.8
Beginning balance (in shares) at Dec. 31, 2023		68,265,042	68,073
Beginning balance at Dec. 31, 2023	3,305.8	$ 68.3	$ (4.1)	2,007.7	1,158.2	(14.8)	90.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	131.6				127.9		3.7
Other comprehensive income, net of tax	2.5					2.5
Dividends on common stock	(44.4)				(44.4)
Share-based compensation (in shares)		104,181	14,270
Share-based compensation	1.4	$ 0.1	$ (0.6)	1.9
Issuance of common stock (in shares)		600,355
Issuance of common stock	31.5	$ 0.6		30.9
Issuance costs	(0.3)			(0.3)
Distributions to non-controlling interest	(5.6)						(5.6)
Ending balance (in shares) at Mar. 31, 2024		68,969,578	82,343
Ending balance at Mar. 31, 2024	$ 3,422.5	$ 69.0	$ (4.7)	$ 2,040.2	$ 1,241.7	$ (12.3)	$ 88.6

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares, issued	68,969,578	68,265,042
Treasury stock, shares	82,343	68,073

Management's Statement (Policies)	3 Months Ended
Management's Statement (Policies)	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Use of Estimates and Basis of Presentation	Use of Estimates and Basis of Presentation The information furnished in the accompanying Consolidated Financial Statements reflects certain estimates required and all adjustments, including accruals, which are, in the opinion of management, necessary for a fair presentation of the March 31, 2024, December 31, 2023 and March 31, 2023 financial information. Certain lines of business in which we operate are highly seasonal, and our interim results of operations are not necessarily indicative of the results of operations to be expected for an entire year.
Recently Issued Accounting Standards	Recently Issued Accounting Standards Improvements to Reportable Segment Disclosures, ASU 2023-07 In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures, which expands public entities’ segment disclosures by requiring disclosure of significant segment expenses that are regularly reviewed by the CODM and included within each reported measure of segment profit or loss, an amount and description of its composition for other segment items, and interim disclosures of a reportable segment’s profit or loss and assets. The ASU also allows, in addition to the measure that is most consistent with GAAP, the disclosure of additional measures of segment profit or loss that are used by the CODM in assessing segment performance and deciding how to allocate resources. The ASU is effective for our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, and subsequent interim periods, with early adoption permitted. We do not expect the ASU to have an impact on our financial position, results of operations and cash flows; however, are currently evaluating the impact on our consolidated financial statement disclosures. Improvements to Income Tax Disclosures, ASU 2023-09 In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures, which expands public entities’ annual disclosures by requiring disclosure of tax rate reconciliation amounts and percentages for specific categories, income taxes paid disaggregated by federal and state taxes, and income tax expense disaggregated by federal and state taxes jurisdiction. The ASU is effective for our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, with early adoption permitted. We do not expect the ASU to have an impact on our financial position, results of operations and cash flows; however, are currently evaluating the impact on our consolidated financial statement disclosures.

Regulatory Matters (Tables)

3 Months Ended

Mar. 31, 2024

Regulated Operations [Abstract]

Schedule of Regulatory Assets and Liabilities

We had the following regulatory assets and liabilities (in millions):


	As of			As of
	March 31, 2024			December 31, 2023
Regulatory assets
Winter Storm Uri	$	144.9		$	199.6
Deferred energy and fuel cost adjustments		57.5			55.1
Deferred gas cost adjustments		8.1			4.1
Gas price derivatives		-			5.1
Deferred taxes on AFUDC		7.4			7.1
Employee benefit plans and related deferred taxes		88.2			89.3
Environmental		5.9			2.9
Loss on reacquired debt		17.0			17.4
Deferred taxes on flow through accounting		80.5			74.7
Decommissioning costs		2.4			2.4
Other regulatory assets		19.2			22.4
Total regulatory assets		431.1			480.1
Less current regulatory assets		(147.3	)		(175.7	)
Regulatory assets, non-current	$	283.8		$	304.4

Regulatory liabilities
Deferred energy and gas costs	$	85.7		$	88.9
Employee benefit plan costs and related deferred taxes		35.7			36.2
Cost of removal		182.2			181.9
Excess deferred income taxes		243.2			247.1
Other regulatory liabilities		6.6			12.5
Total regulatory liabilities		553.4			566.6
Less current regulatory liabilities		(89.9	)		(98.9	)
Regulatory liabilities, non-current	$	463.5		$	467.7

Selected Balance Sheet Information (Tables)

3 Months Ended

Mar. 31, 2024

Selected Balance Sheet Information [Abstract]

Account Receivable Schedule

Following is a summary of Accounts receivable, net included in the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024			December 31, 2023
Billed Accounts Receivable	$	216.1		$	198.5
Unbilled Revenue		122.2			154.0
Less: Allowance for Credit Losses		(3.9	)		(2.2	)
Account Receivable, net	$	334.4		$	350.3

Financing Receivable, Current, Allowance for Credit Loss

Changes to allowance for credit losses for the three months ended March 31, 2024 and 2023, respectively, were as follows (in millions):


	Balance at Beginning of Year		Additions Charged to Costs and Expenses		Recoveries and Other Additions		Write-offs and Other Deductions			Balance at March 31,
2024	$	2.2	$	2.0	$	1.1	$	(1.4	)	$	3.9
2023	$	3.0	$	3.7	$	0.6	$	(1.9	)	$	5.4

Materials, Supplies and Fuel

The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024		December 31, 2023
Materials and supplies	$	107.4	$	105.9
Fuel - Electric Utilities		7.5		7.7
Natural gas in storage		15.7		47.3
Total materials, supplies and fuel	$	130.6	$	160.9

Schedule of Accrued Liabilities

The following amounts by major classification are included in Accrued liabilities on the accompanying Consolidated Balance Sheets (in millions) as of:


	March 31, 2024		December 31, 2023
Accrued employee compensation, benefits and withholdings	$	52.2	$	74.8
Accrued property taxes		55.8		52.7
Customer deposits and prepayments		60.3		76.0
Accrued interest		56.0		46.3
Other (none of which is individually significant)		39.6		43.5
Total accrued liabilities	$	263.9	$	293.3

Revenue: Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue from contracts with customers	$ 717.2	$ 912.1
Revenue	726.4	921.2
Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	625.7	810.4
Transportation
Revenue from contracts with customers	51.6	52.7
Wholesale
Revenue from contracts with customers	8.5	9.4
Market - off-system sales
Revenue from contracts with customers	6.6	16.4
Transmission/Other
Revenue from contracts with customers	24.8	23.2
Other revenues
Revenue	9.2	9.1
Services transferred at a point in time
Revenue from contracts with customers	8.7	8.7
Services transferred over time
Revenue from contracts with customers	708.5	903.4
Inter-segment Eliminations
Revenue from contracts with customers	(4.5)	(4.4)
Revenue	(4.5)	(4.4)
Inter-segment Eliminations \| Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	0.0	0.0
Inter-segment Eliminations \| Transportation
Revenue from contracts with customers	(0.1)	(0.1)
Inter-segment Eliminations \| Wholesale
Revenue from contracts with customers	0.0	0.0
Inter-segment Eliminations \| Market - off-system sales
Revenue from contracts with customers	0.0	0.0
Inter-segment Eliminations \| Transmission/Other
Revenue from contracts with customers	(4.4)	(4.3)
Inter-segment Eliminations \| Other revenues
Revenue	0.0	0.0
Inter-segment Eliminations \| Services transferred at a point in time
Revenue from contracts with customers	0.0	0.0
Inter-segment Eliminations \| Services transferred over time
Revenue from contracts with customers	(4.5)	(4.4)
Operating Segments \| Electric Utilities
Revenue from contracts with customers	221.4	217.8
Revenue	222.2	218.7
Operating Segments \| Electric Utilities \| Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	188.3	174.9
Operating Segments \| Electric Utilities \| Transportation
Revenue from contracts with customers	0.0	0.0
Operating Segments \| Electric Utilities \| Wholesale
Revenue from contracts with customers	8.5	9.4
Operating Segments \| Electric Utilities \| Market - off-system sales
Revenue from contracts with customers	6.6	16.1
Operating Segments \| Electric Utilities \| Transmission/Other
Revenue from contracts with customers	18.0	17.4
Operating Segments \| Electric Utilities \| Other revenues
Revenue	0.8	0.9
Operating Segments \| Electric Utilities \| Services transferred at a point in time
Revenue from contracts with customers	8.7	8.7
Operating Segments \| Electric Utilities \| Services transferred over time
Revenue from contracts with customers	212.7	209.1
Operating Segments \| Gas Utilities
Revenue from contracts with customers	500.3	698.7
Revenue	508.7	706.9
Operating Segments \| Gas Utilities \| Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	437.4	635.5
Operating Segments \| Gas Utilities \| Transportation
Revenue from contracts with customers	51.7	52.8
Operating Segments \| Gas Utilities \| Wholesale
Revenue from contracts with customers	0.0	0.0
Operating Segments \| Gas Utilities \| Market - off-system sales
Revenue from contracts with customers	0.0	0.3
Operating Segments \| Gas Utilities \| Transmission/Other
Revenue from contracts with customers	11.2	10.1
Operating Segments \| Gas Utilities \| Other revenues
Revenue	8.4	8.2
Operating Segments \| Gas Utilities \| Services transferred at a point in time
Revenue from contracts with customers	0.0	0.0
Operating Segments \| Gas Utilities \| Services transferred over time
Revenue from contracts with customers	$ 500.3	$ 698.7

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 123.0	$ 86.6
Restricted cash and equivalents	6.7	6.4
Accounts receivable, net	334.4	350.3
Materials, supplies and fuel	130.6	160.9
Income tax receivable, net	18.2	18.5
Regulatory assets, current	147.3	175.7
Other current assets	37.4	28.2
Total current assets	797.6	826.6
Property, plant and equipment	9,068.4	8,917.2
Less accumulated depreciation	(1,845.3)	(1,797.9)
Total property, plant and equipment, net	7,223.1	7,119.3
Other assets:
Goodwill	1,299.5	1,299.5
Intangible assets, net	8.4	8.4
Regulatory assets, non-current	283.8	304.4
Other assets, non-current	64.3	62.2
Total other assets, non-current	1,656.0	1,674.5
TOTAL ASSETS	9,676.7	9,620.4
Current liabilities:
Accounts payable	132.6	186.4
Accrued liabilities	263.9	293.3
Derivative liabilities, current	2.0	6.5
Regulatory liabilities, current	89.9	98.9
Notes payable	0.0	0.0
Current maturities of long-term debt	600.0	600.0
Total current liabilities	1,088.4	1,185.1
Long-term debt, net of current maturities	3,802.8	3,801.2
Deferred credits and other liabilities:
Deferred income tax liabilities, net	576.1	548.0
Regulatory liabilities, non-current	463.5	467.7
Benefit plan liabilities	124.1	123.9
Other deferred credits and other liabilities	199.3	188.7
Total deferred credits and other liabilities	1,363.0	1,328.3
Commitments, contingencies and guarantees (Note 3)
Equity:
Common stock $1 par value; 100,000,000 shares authorized; issued 68,969,578 and 68,265,042 shares, respectively	69.0	68.3
Additional paid-in capital	2,040.2	2,007.7
Retained earnings	1,241.7	1,158.2
Treasury stock, at cost - 82,343 and 68,073 shares, respectively	(4.7)	(4.1)
Accumulated other comprehensive income (loss)	(12.3)	(14.8)
Total stockholders’ equity	3,333.9	3,215.3
Non-controlling interest	88.6	90.5
Total equity	3,422.5	3,305.8
TOTAL LIABILITIES AND TOTAL EQUITY	$ 9,676.7	$ 9,620.4

Risk Management And Derivatives (Tables)

3 Months Ended

Mar. 31, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Contract or notional amounts and terms of marketing activities and derivative commodity instruments


	March 31, 2024					December 31, 2023
	Notional Amounts (MMBtus)			Maximum Term (months) (a)		Notional Amounts (MMBtus)		Maximum Term (months) (a)
Natural gas futures purchased		-		N/A			650,000		3
Natural gas options purchased, net		-		N/A			2,850,000		3
Natural gas basis swaps purchased		-		N/A			1,050,000		3
Natural gas over-the-counter swaps, net (b)		2,600,000			20		3,890,000		21
Natural gas physical contracts, net (c)		(444,110	)		7		12,582,415		10

(a)

Term reflects the maximum forward period hedged.

(b)

As of March 31, 2024, 695,000 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges.

(c)

Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value

The following table presents the fair value and balance sheet classification of our derivative instruments (in millions) as of:


	Balance Sheet Location	March 31, 2024			December 31, 2023
Derivatives designated as hedges:
Liability derivative instruments:
Current commodity derivatives	Derivative liabilities, current	$	(0.7	)	$	(2.7	)
Noncurrent commodity derivatives	Other assets, non-current		(0.1	)		(0.2	)
Total derivatives designated as hedges		$	(0.8	)	$	(2.9	)

Derivatives not designated as hedges:
Liability derivative instruments:
Current commodity derivatives	Derivative liabilities, current	$	(1.3	)	$	(3.8	)
Noncurrent commodity derivatives	Other deferred credits and other liabilities		-			(0.1	)
Total derivatives not designated as hedges		$	(1.3	)	$	(3.9	)

Derivative Instruments, Gain (Loss)


	Three Months Ended March 31,					Three Months Ended March 31,
	2024		2023			2024			2023
Derivatives in Cash Flow Hedging Relationships	Amount of Gain/(Loss) Recognized in OCI				Income Statement Location	Amount of Gain/(Loss) Reclassified from AOCI into Income
	(in millions)					(in millions)
Interest rate swaps	$	0.7	$	0.7	Interest expense	$	(0.7	)	$	(0.7	)
Commodity derivatives		2.4		0.8	Fuel, purchased power and cost of natural gas sold		(2.6	)		(2.0	)
Total	$	3.1	$	1.5		$	(3.3	)	$	(2.7	)

Derivatives Not Designated as Hedge Instruments


		Three Months Ended March 31,
		2024		2023
Derivatives Not Designated as Hedging Instruments	Location of Gain/(Loss) on Derivatives Recognized in Income	Amount of Gain/(Loss) on Derivatives Recognized in Income
		(in millions)
Commodity derivatives	Fuel, purchased power and cost of natural gas sold	$	0.6	$	(3.1	)
		$	0.6	$	(3.1	)

Earnings Per Share

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Earnings Per Share

(6)

Earnings Per Share

A reconciliation of share amounts used to compute earnings per share in the accompanying Consolidated Statements of Income was as follows (in millions, except per share amounts):


	Three Months Ended March 31,
	2024		2023
Net income available for common stock	$	127.9	$	114.1

Weighted average shares - basic		68.2		66.0
Dilutive effect of equity compensation		0.1		0.1
Weighted average shares - diluted		68.3		66.1

Net income available for common stock, per share - Diluted	$	1.87	$	1.73

The following securities were excluded from the diluted earnings per share computation because of their anti-dilutive nature (in millions of shares):

Selected Balance Sheet Information: Materials, Supplies, and Fuel Schedule (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Selected Balance Sheet Information [Abstract]
Materials and supplies	$ 107.4	$ 105.9
Fuel - Electric Utilities	7.5	7.7
Natural gas in storage	15.7	47.3
Total materials, supplies and fuel	$ 130.6	$ 160.9

Selected Balance Sheet Information: Changes to Allowance for Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Selected Balance Sheet Information [Abstract]
Balance at Beginning of Year	$ 2.2	$ 3.0
Additions Charged to Costs and Expenses	2.0	3.7
Recoveries and Other Additions	1.1	0.6
Write-offs and Other Deductions	(1.4)	(1.9)
Balance at End of Year	$ 3.9	$ 5.4

Financing: At-the-Market Equity Offering Program (Details) - Common Stock - USD ($) $ / shares in Units, shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Proceeds, (net of issuance costs)	$ 31,200,000	$ 27,400,000
Average price per share	$ 52.51	$ 62.21
Number of shares issued	0.6	0.4
Payments of Stock Issuance Costs	$ (300,000)	$ (300,000)
August 4, 2020 ATM Program
Proceeds, (net of issuance costs)	$ 0	$ 27,400,000
Number of shares issued	0.0	0.4
Payments of Stock Issuance Costs	$ 0	$ (0.3)
June 16, 2023 ATM Program
Proceeds, (net of issuance costs)	$ 31,200,000	$ 0
Number of shares issued	0.6	0.0
Payments of Stock Issuance Costs	$ (0.3)	$ 0

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 127.9	$ 114.1

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Subsequent Events

3 Months Ended

Mar. 31, 2024

Subsequent Events [Abstract]

Subsequent Events

(14)

Subsequent Events

Except as described in Note 2, there have been no events subsequent to March 31, 2024, which would require recognition in the Consolidated Financial Statements or disclosures.

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2024	Apr. 30, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Current Fiscal Year End Date	--12-31
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-31303
Entity Registrant Name	Black Hills Corporation
Entity Incorporation, State or Country Code	SD
Entity Tax Identification Number	46-0458824
Entity Address, Address Line One	7001 Mount Rushmore Road
Entity Address, City or Town	Rapid City
Entity Address, State or Province	SD
Entity Address, Postal Zip Code	57702
City Area Code	605
Local Phone Number	721-1700
Title of 12(b) Security	Common stock of $1.00 par value
Trading Symbol	BKH
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		68,933,306
Entity Central Index Key	0001130464
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1

Risk Management and Derivatives: Derivatives Not Designated as Hedge Instruments (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Derivative [Line Items]
Regulatory assets	$ 431,100,000		$ 480,100,000
Regulatory liabilities	553,400,000		566,600,000
Gas price derivatives
Derivative [Line Items]
Regulatory assets	0		$ 5,100,000
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 600	$ (3,100)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold
Not Designated as Hedging Instrument \| Natural Gas
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 600	$ (3,100)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold

Fair Value Measurements: Schedule of Fair Values (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Derivative Liability, Current	Derivative Liability, Current
Contract Subject to Master Netting
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 1.9
Derivative Liability, Fair Value, Gross Liability		3.3
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	$ 0.0	(1.9)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0.0	(3.3)
Fair Value, Measurements, Recurring \| Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	2.1	6.8
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	0.0	0.0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	1.9
Derivative, Liabilities, Fair Value Disclosure	2.1	10.1
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	0.0	0.0
Fair Value, Measurements, Recurring \| Gas Utilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset		(1.9)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset		(3.3)
Fair Value, Measurements, Recurring \| Gas Utilities \| Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	2.1	6.8
Fair Value, Measurements, Recurring \| Gas Utilities \| Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	0.0	0.0
Fair Value, Measurements, Recurring \| Gas Utilities \| Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	1.9
Derivative, Liabilities, Fair Value Disclosure	2.1	10.1
Fair Value, Measurements, Recurring \| Gas Utilities \| Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0.0	0.0
Derivative, Liabilities, Fair Value Disclosure	$ 0.0	$ 0.0

Other Comprehensive Income: Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	$ (14.8)	$ (15.6)
Other comprehensive income (loss), before reclassifications	(0.1)	(0.9)
Amounts reclassified from AOCI	2.6	2.1
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(12.3)	(14.4)
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(6.2)	(6.1)
Other comprehensive income (loss), before reclassifications	0.0	0.0
Amounts reclassified from AOCI	0.0	0.0
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(6.2)	(6.1)
Interest Rate Swap \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(6.1)	(8.3)
Other comprehensive income (loss), before reclassifications	0.0	0.0
Amounts reclassified from AOCI	0.6	0.6
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(5.5)	(7.7)
Commodity Contract \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(2.5)	(1.2)
Other comprehensive income (loss), before reclassifications	(0.1)	(0.9)
Amounts reclassified from AOCI	2.0	1.5
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	$ (0.6)	$ (0.6)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

+ References + Details

Risk Management and Derivatives: Cash Flow Hedges (Details) - Cash Flow Hedging - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest rate swaps
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 3.6
Designated as Hedging Instrument
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	3.1	$ 1.5
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (3.3)	$ (2.7)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest
Designated as Hedging Instrument \| Interest rate swaps
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ 0.7	$ 0.7
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ (0.7)	$ (0.7)
Derivative Instrument, Loss Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Costs Incurred	Interest Costs Incurred
Designated as Hedging Instrument \| Commodity Contract
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ 2.4	$ 0.8
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ (2.6)	$ (2.0)
Derivative Instrument, Gain Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold

Earnings Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from computation of earnings per share	0.1	0.1
Share-Based Payment Arrangement [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from computation of earnings per share	0.1	0.1
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from computation of earnings per share	0.0	0.0

Business Segment Information (Tables)

3 Months Ended

Mar. 31, 2024

Segment Reporting Information, Additional Information [Abstract]

Segment information included in Consolidated Statements of Income

Segment information was as follows (in millions):


	Electric Utilities		Gas Utilities		Corporate and Other			Total
Three Months Ended March 31, 2024
External revenues	$	219.3	$	507.1	$	-		$	726.4
Inter-segment revenues		2.9		1.6		(4.5	)		-
Operating income		64.6		130.8		(2.1	)		193.3
Capital expenditures (a)		86.9		85.0		2.4			174.3
Three Months Ended March 31, 2023
External revenues	$	215.9	$	705.3	$	-		$	921.2
Inter-segment revenues		2.8		1.6		(4.4	)		-
Operating income		61.1		114.6		(0.8	)		174.9
Capital expenditures (a)		47.8		54.8		1.1			103.7

(a)

Includes accruals for property, plant and equipment as disclosed in supplemental cash flow information in the Consolidated Statements of Cash Flows in the Consolidated Financial Statements.

Fair Value Measurements: Other Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, including current maturities	$ 4,402.8	$ 4,401.2
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, including current maturities	$ 4,155.6	$ 4,215.6

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue:
Revenue	$ 726.4	$ 921.2
Operating expenses:
Fuel, purchased power and cost of natural gas sold	316.6	526.3
Operations and maintenance	133.6	141.0
Depreciation and amortization	65.9	61.6
Taxes - property and production	17.0	17.4
Total operating expenses	533.1	746.3
Operating income	193.3	174.9
Other income (expense):
Interest expense incurred net of amounts capitalized	(46.0)	(44.1)
Interest income	2.0	0.6
Other income (expense), net	(0.8)	0.7
Total other income (expense)	(44.8)	(42.8)
Income before income taxes	148.5	132.1
Income tax (expense)	(16.9)	(14.7)
Net income	131.6	117.4
Net income attributable to non-controlling interest	(3.7)	(3.3)
Net income available for common stock	$ 127.9	$ 114.1
Earnings per share of common stock:
Earnings per share, Basic (usd per share)	$ 1.88	$ 1.73
Earnings per share, Diluted (usd per share)	$ 1.87	$ 1.73
Weighted average common shares outstanding:
Basic (in shares)	68.2	66.0
Diluted (in shares)	68.3	66.1