IPUC (Details) - Gas Distribution [Member] - IPUC - Intermountain Gas Company - USD ($) $ in Millions	Jun. 30, 2023	Mar. 09, 2023	Dec. 01, 2022
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount			$ 11.3
Public Utilities, Requested Rate Increase (Decrease), Percentage			3.20%
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 3.1	$ 6.8
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage	0.70%	1.90%

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

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

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