Commitments and Contingencies - Schedule of Gas Purchase and Pipeline Capacity Purchase and Release Commitments (Details) - Northwest Natural Gas Company [Member] $ in Thousands	Dec. 31, 2022 USD ($)
Gas Purchase Agreements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2018	$ 400,370
2019	6,376
2020	6,426
2021	12,003
2022	11,330
Thereafter	189,050
Total	625,555
Less: Amount representing interest	86,250
Total at present value	539,305
Pipeline Capacity Purchase Agreements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2018	81,691
2019	77,327
2020	78,493
2021	66,782
2022	66,906
Thereafter	432,464
Total	803,663
Less: Amount representing interest	200,243
Total at present value	603,420
Pipeline Capacity Release Agreements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2018	8,154
2019	7,474
2020	3,397
2021	0
2022	0
Thereafter	0
Total	19,025
Less: Amount representing interest	989
Total at present value	$ 18,036