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Regulatory Matters: Tax Cut and Jobs Act (Details) - USD ($) $ in Thousands		1 Months Ended
	Jan. 01, 2022	Apr. 30, 2021	Jan. 26, 2021	Dec. 30, 2020
Colorado Public Utilities Commission (CPUC) | Colorado Electric
Public Utilities, General Disclosures [Line Items]
Settlement of plan to provide TCJA-related customer billing credits to its customers				$ 9,300
Annual TCJA-Related Customer Billing Credits		$ 900
Nebraska Public Service Commission (NPSC) | Nebraska Gas
Public Utilities, General Disclosures [Line Items]
Settlement of plan to provide TCJA-related customer billing credits to its customers			$ 2,900
Kansas Corporation Commission (KCC) | Kansas Gas | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Settlement of Plan to Provide TCJA and State Tax Reform benefits to Customers Annually	$ 3,000
Number of Years TCJA and State Tax Reform Benefits to be Provide to Customers	3 years
Settlement Total of Plan to Provide TCJA and State Tax Reform benefits to Customers	$ 9,100

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Annual TCJA-Related Customer Billing Credits

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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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