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Weighted Average Cost of Capital

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Percentage of public utility's approved debt to capital, including debt and equity.

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Percentage of public utility's approved equity to capital, including debt and equity.

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Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved return on equity.

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Percentage of public utility's requested debt to capital, including debt and equity.

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Percentage of public utility's requested equity to capital, including debt and equity.

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Regulatory Matters: Gas and Electric Utilities Recent Regulatory Activity (Details) $ in Millions							3 Months Ended
	Dec. 09, 2025 USD ($)	Dec. 05, 2025 USD ($) mi	Jul. 24, 2025 USD ($)	May 06, 2025 USD ($)	May 05, 2025 USD ($)	Mar. 17, 2025 USD ($)	Dec. 31, 2024 USD ($)	May 01, 2025 mi	Feb. 03, 2025 mi	Jun. 14, 2024 mi	May 01, 2024 mi
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Electric
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount \| $				$ 17.5	$ 17.0	$ 17.0
Weighted average cost of capital						6.90%
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Electric \| Minimum
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage						47.00%
Public Utilities, Approved Debt Capital Structure, Percentage						51.00%
Public Utilities, Approved Return on Equity, Percentage						9.30%
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Electric \| Maximum
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage						49.00%
Public Utilities, Approved Debt Capital Structure, Percentage						53.00%
Public Utilities, Approved Return on Equity, Percentage						9.50%
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Electric \| Rate Review Filed with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Electric Distribution Lines to Receive Infrastructure Investments \| mi										3,200
Public Utilities - Length of Electric Transmission Lines to Receive Infrastructure Investments \| mi										600
Iowa Utilities Commission (IUC) \| Black Hills Energy - Iowa Gas
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount \| $							$ 15.0
Weighted average cost of capital							7.20%
Iowa Utilities Commission (IUC) \| 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
Kansas Corporation Commission (KCC) \| Black Hills Energy, Kansas Gas
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount \| $			$ 10.8
Kansas Corporation Commission (KCC) \| Black Hills Energy, Kansas 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									4,765
Kansas Corporation Commission (KCC) \| Black Hills Energy, Kansas Gas \| GSRS Rider Revenue
Public Utilities, General Disclosures [Line Items]
Public Utilities, Amount of System Safety and Integrity Rider Moved to Base Rates \| $			$ 4.4
Nebraska Publc Service Commission (NPSC) \| Black Hills Energy - Nebraska 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								12,900
Nebraska Publc Service Commission (NPSC) \| Black Hills Energy - Nebraska Gas \| Received Final Approval for a Settlement Agreement for a General Rate Increase
Public Utilities, General Disclosures [Line Items]
Public utilities, requested equity capital structure, percentage	51.00%
Public utilities, requested debt capital structure, percentage	49.00%
Public Utilities, Approved Return on Equity, Percentage	9.85%
Public Utilities, Approved Rate Increase (Decrease), Amount \| $	$ 23.9
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, Approved Equity Capital Structure, Percentage		50.00%
Public Utilities, Approved Debt Capital Structure, Percentage		50.00%
Public Utilities, Approved Return on Equity, Percentage		10.50%
Public Utilities, Approved Rate Increase (Decrease), Amount \| $		$ 29.4