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Supplemental Cash Flow - USD ($) $ in Thousands	3 Months Ended
Supplemental Cash Flow - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents		$ 140,821	$ 29,270	$ 24,325
Restricted Cash		15,173	11,694	11,318
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents		155,994	40,964	35,643	$ 27,120
Money Market Funds, at Carrying Value		112,600
Northwest Natural Gas Company [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents		129,731	12,977	10,165
Restricted Cash		15,173	11,694	11,318
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents		144,904	$ 24,671	$ 21,483	$ 20,832
Money Market Funds, at Carrying Value		$ 107,600
Northwest Natural Gas Company [Member] \| Subsequent Event [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Payments of Dividends	$ 25,000