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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of increase in the fair value of derivatives recognized in the income statement.

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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.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Unrealized and Realized Gain/Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Unrealized and Realized Gain/Loss - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative [Line Items]
Derivative, Gain on Derivative	$ 21,200		$ 153,200	$ 57,200
Derivative, Gain (Loss) on Derivative, Net	1,236		825	0
Derivative, Loss on Derivative	19,200
Financial [Member]
Derivative [Line Items]
Incremental Cost or Benefit to Collect or Refund to Customers			0
Northwest Holdings and Northwest Natural [Member] \| Natural gas commodity
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	$ 0	0	0
Northwest Holdings and Northwest Natural [Member] \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	0	0	0
Northwest Holdings and Northwest Natural [Member] \| Benefit (expense) to cost of gas \| Natural gas commodity
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(11,936)	29,332	(73,257)	(44,453)
Northwest Holdings and Northwest Natural [Member] \| Benefit (expense) to cost of gas \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	168	(153)	181	(73)
Northwest Holdings and Northwest Natural [Member] \| Sales [Member] \| Natural gas commodity
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	0	0	0
Northwest Holdings and Northwest Natural [Member] \| Sales [Member] \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	0	0	0
Deferred Derivative Gain (Loss) [Member] \| Northwest Holdings and Northwest Natural [Member] \| Natural gas commodity
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	11,936	29,332	73,257	(44,453)
Deferred Derivative Gain (Loss) [Member] \| Northwest Holdings and Northwest Natural [Member] \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ (168)	$ 153	$ (181)	$ 73