OPUC (Details 4) - OPUC - Pending Rate Case [Member] - Gas Distribution [Member] - Cascade Natural Gas [Member] - USD ($)	Feb. 01, 2021	Mar. 31, 2020
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 4,900,000
Public Utilities, Requested Rate Increase (Decrease), Percentage		7.20%
Environmental Remediation Deferred Costs Increase (Decrease) Amount		$ 364,000
Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 3,200,000
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage	4.80%

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