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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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