WUTC (Details 4) - Pipeline Cost Recovery Mechanism - WUTC [Member] - Cascade Natural Gas [Member] - USD ($) $ in Millions	Oct. 13, 2023	Jun. 01, 2023
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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Amount of public utility's amended requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's amended requested rate increase (decrease) with regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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