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IPUC (Details) - Pending Rate Case [Member] - IPUC - Intermountain Gas - Gas Distribution [Member] - USD ($) $ in Millions	Jun. 03, 2021	Jan. 12, 2021
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%
Depreciation and Amortization Requested Rate Increase (Decrease), Amended Amount	$ (3.8)
Depreciation and Amortization, Requested Rate, Amended, Percent	2.40%

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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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