WUTC (Details 3) - Pending Rate Case [Member] - Gas Distribution [Member] - WUTC [Member] - Cascade Natural Gas [Member] - USD ($) $ in Millions	Mar. 24, 2022	Mar. 22, 2022	Sep. 30, 2021
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 3.3		$ 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%

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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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