Regulatory matters - IPUC (Details) - Natural gas distribution - IPUC - Intermountain Gas Company $ in Millions	May 30, 2025 USD ($)
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount	$ 26.5
Public utilities, requested rate increase (decrease), percentage	8.60%

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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