- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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- Details

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- Details

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- Details

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WUTC (Details 5) - Pending Rate Case [Member] - WUTC [Member] - Cascade Natural Gas [Member] - USD ($) $ in Millions	Oct. 15, 2021	Sep. 30, 2021	Jun. 01, 2021
Pipeline Cost Recovery Mechanism [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			$ 2.1
Public Utilities, Requested Rate Increase (Decrease), Percentage			0.80%
Pipeline Cost Recovery Mechanism [Member] \| Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 1.7
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage	0.60%
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%