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IPUC (Details) - Gas Distribution [Member] - IPUC - Intermountain Gas Company - USD ($) $ in Millions | Jun. 30, 2023 | Mar. 09, 2023 | Dec. 01, 2022
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Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  | $ 11.3
Public Utilities, Requested Rate Increase (Decrease), Percentage |  |  | 3.20%
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount | $ 3.1 | $ 6.8 |
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage | 0.70% | 1.90% |

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