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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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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

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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Unrealized and Realized Gain/Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Unrealized and Realized Gain/Loss - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financial [Member]
Derivative [Line Items]
Derivative, Gain on Derivative	$ 0			$ 9,200
Derivative, Loss on Derivative	0	$ (1,100)	$ (3,200)
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	(96)	(291)	148	(7)
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	(28,122)	2,391	(28,271)	4,255
Northwest Holdings and Northwest Natural [Member] \| Benefit (expense) to cost of gas \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(136)	133	(129)	(24)
Northwest Holdings and Northwest Natural [Member] \| Sales [Member] \| Natural gas commodity
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(658)	(2,002)	1,021	(36)
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	28,684	4,102	27,398	4,284
Deferred Derivative Gain (Loss) [Member] \| Northwest Holdings and Northwest Natural [Member] \| Foreign exchange
Derivative [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 136	$ (133)	$ 129	$ 24