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Regulatory Matters: Gas Utilities Regulatory Activity (Details) $ in Millions					1 Months Ended
	Jun. 14, 2024 USD ($) mi	May 01, 2024 USD ($) mi	Jan. 17, 2024 USD ($)	Dec. 04, 2023 USD ($) mi	Mar. 31, 2024 USD ($)	May 18, 2023 mi	May 09, 2023 mi
Colorado Public Utilities Commission (CPUC) \| Black Hills Energy - Colorado Gas \| Settlement Reached with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Natural Gas Pipeline to Receive Infrastructure Investments							10,000
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
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	3,200
Public Utilities - Length of Electric Transmission Lines to Receive Infrastructure Investments	600
Public Utilities, Requested Rate Increase (Decrease), Amount \| $	$ 36.7
Public Utilities, Approved Equity Capital Structure, Percentage	53.00%
Public Utilities, Approved Debt Capital Structure, Percentage	47.00%
Public Utilities, Approved Return on Equity, Percentage	10.50%
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		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				7,200
Public Utilities, Requested Rate Increase (Decrease), Amount \| $				$ 44.1
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						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