IPUC (Details) - Pending Rate Case [Member] - IPUC - Intermountain Gas - Gas Distribution [Member] $ in Millions	Jan. 12, 2021 USD ($)
Public Utilities, General Disclosures [Line Items]
Depreciation and Amortization Rate Case	$ (2.9)
Depreciation and Amortization, Rate, Percent	3.00%
Depreciation and Amortization, Requested Rate, Percent	2.60%

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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