Public Utilities Amount of System Safety and Integrity Rider Moved to Base Rates

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Public Utilities - Length of Electric Distribution Lines to Receive Infrastructure Investments

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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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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.

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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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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested return on equity.

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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477571/980-405-25-1

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Regulatory Matters: Gas Utilities Regulatory Activity (Details) $ in Millions						3 Months Ended
	Jul. 24, 2025 USD ($)	May 06, 2025 USD ($)	May 05, 2025 USD ($)	May 01, 2025 USD ($) mi	Mar. 17, 2025 USD ($)	Dec. 31, 2024 USD ($)	Jun. 30, 2025 USD ($)	Feb. 03, 2025 mi	Jun. 14, 2024 mi	May 01, 2024 mi
Public Utilities, General Disclosures [Line Items]
Regulatory liability						$ 568.7	$ 576.7
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Electric
Public Utilities, General Disclosures [Line Items]
Weighted average cost of capital					6.90%
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 17.5	$ 17.0		$ 17.0
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]
Weighted average cost of capital						7.20%
Public Utilities, Approved Rate Increase (Decrease), Amount						$ 15.0
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 \| 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
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
Public Utilities, Requested Rate Increase (Decrease), Amount				$ 34.9
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%
Subsequent Event \| Kansas Corporation Commission (KCC) \| Black Hills Energy, Kansas Gas
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 10.8
Subsequent Event \| 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