Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved rate increase (decrease) by regulatory agency.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

+ References

No definition available.

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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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No definition available.

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

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No definition available.

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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
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