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WUTC (Details 3) - WUTC [Member] - Cascade Natural Gas [Member] - USD ($) $ in Millions | Nov. 01, 2022 | Sep. 01, 2022 | Mar. 24, 2022 | Mar. 22, 2022 | Sep. 30, 2021
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Gas Distribution [Member] |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  |  |  | $ 13.7
Public Utilities, Requested Rate Increase (Decrease), Percentage |  |  |  |  | 5.10%
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount |  |  |  | $ 10.7 |
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage |  |  |  | 4.00% |
Public Utilities, Approved Rate Increase (Decrease), Amount |  | $ 7.2 |  |  |
Pipeline Cost Recovery Mechanism | Subsequent Event [Member] |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Public Utilities, Approved Rate Increase (Decrease), Amount | $ 1.2 |  |  |  |
Public Utilities, Approved Rate Increase (Decrease), Percentage | 0.40% |  |  |  |
Pending Rate Case [Member] | Gas Distribution [Member] |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  | $ 3.3 |  |

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