The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details) - USD ($) $ in Thousands			1 Months Ended			12 Months Ended
Subsequent Events (Details) - USD ($) $ in Thousands	Jan. 19, 2024	Dec. 05, 2023	May 31, 2023	Apr. 30, 2023	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 20, 2023
Subsequent Event [Line Items]
Repayment of short-term borrowings						$ 460,901	$ 0	$ 100,000
Short-term borrowings						$ 95,000	$ 38,500
Cascade Natural Gas \| Term Loan Agreement
Subsequent Event [Line Items]
Repayment of short-term borrowings		$ 100,000
Short-term borrowings									$ 150,000
Cascade Natural Gas \| Subsequent Event \| Term Loan Agreement
Subsequent Event [Line Items]
Repayment of short-term borrowings	$ 50,000
Intermountain Gas Company \| Term Loan Agreement
Subsequent Event [Line Items]
Repayment of short-term borrowings			$ 30,000	$ 30,000	$ 20,000
Short-term borrowings									$ 125,000
Intermountain Gas Company \| Subsequent Event \| Term Loan Agreement
Subsequent Event [Line Items]
Repayment of short-term borrowings	$ 45,000