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WUTC (Details 4) - Pipeline Cost Recovery Mechanism - WUTC [Member] - Cascade Natural Gas [Member] - USD ($) $ in Millions | Oct. 13, 2023 | Jun. 01, 2023
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Public Utilities, General Disclosures [Line Items] |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  | $ 3.1
Public Utilities, Requested Rate Increase (Decrease), Percentage |  | 0.90%
Subsequent Event [Member] |  |
Public Utilities, General Disclosures [Line Items] |  |
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount | $ 2.4 |
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage | 0.70% |

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