Derivative Instruments - Schedule of Unrealized and Realized Gain/Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Derivative, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration]	Operating revenues	Operating revenues
Northwest Holdings and Northwest Natural [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 0	$ 0
Northwest Holdings and Northwest Natural [Member] | Foreign Exchange Contract [Member] | Cost of Sales [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(165)	(26)
Northwest Holdings and Northwest Natural [Member] | Foreign Exchange Contract [Member] | Sales [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	0
Northwest Holdings and Northwest Natural [Member] | Natural Gas Commodity [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	(4)
Northwest Holdings and Northwest Natural [Member] | Natural Gas Commodity [Member] | Cost of Sales [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	119,935	(36,539)
Northwest Holdings and Northwest Natural [Member] | Natural Gas Commodity [Member] | Sales [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	(26)
Northwest Holdings and Northwest Natural [Member] | Deferred Derivative Gain (Loss) [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	165	26
Northwest Holdings and Northwest Natural [Member] | Deferred Derivative Gain (Loss) [Member] | Natural Gas Commodity [Member]
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ (119,935)	$ (36,517)