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Regulatory Matters: Regulatory Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 26, 2021	Dec. 30, 2020
Benefit from Relieved TCJA Related Liabilities	$ 4,000
Colorado Public Utilities Commission (CPUC) | Black Hills Energy - Colorado Electric
Settlement of plan to provide TCJA-related customer billing credits to its customers			$ 9,300
Nebraska Public Service Commission (NPSC) | Black Hills Energy - Nebraska Gas | Subsequent Event
Settlement of plan to provide TCJA-related customer billing credits to its customers		$ 2,900

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Benefit from Relieved TCJA Related Liabilities

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Settlement of plan to provide TCJA-related customer billing credits to its customers. The billing credits, which represent a disposition of excess deferred income tax benefits resulting from the TCJA, will be delivered to customers in the next fiscal year.

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