Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Lessee, Lease, Description [Line Items]
Operating cash flows from operating leases	$ 4,304	$ 4,241
Right of use assets obtained in exchange for lease obligations
Operating leases	1,711	2,647
NW Natural
Lessee, Lease, Description [Line Items]
Operating cash flows from operating leases	3,880	3,753
Right of use assets obtained in exchange for lease obligations
Operating leases	$ 250	$ 346

Right Of Use Assets Obtained In Exchange For Lease Obligations

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- Definition

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.

+ References

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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