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No definition available.

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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

+ Details

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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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Derivative Instruments Notional Amounts - Northwest Natural Gas Company [Member] therm in Thousands, $ in Thousands	Sep. 30, 2023 USD ($) therm	Dec. 31, 2022 USD ($) therm	Sep. 30, 2022 USD ($) therm
Gas Year 2021-2022
Derivative [Line Items]
TargetHedgeAchieved	84.00%
Gas Year 2021-2022 \| Oregon [Member]
Derivative [Line Items]
TargetHedgeAchieved	85.00%
Gas Year 2021-2022 \| WASHINGTON
Derivative [Line Items]
TargetHedgeAchieved	79.00%
Financial [Member] \| Gas Year 2021-2022
Derivative [Line Items]
TargetHedgeAchieved	67.00%
Financial [Member] \| Gas Year 2021-2022 \| Oregon [Member]
Derivative [Line Items]
TargetHedgeAchieved	67.00%
Financial [Member] \| Gas Year 2021-2022 \| WASHINGTON
Derivative [Line Items]
TargetHedgeAchieved	66.00%
Physical [Member] \| Gas Year 2021-2022
Derivative [Line Items]
TargetHedgeAchieved	17.00%
Physical [Member] \| Gas Year 2021-2022 \| Oregon [Member]
Derivative [Line Items]
TargetHedgeAchieved	18.00%
Physical [Member] \| Gas Year 2021-2022 \| WASHINGTON
Derivative [Line Items]
TargetHedgeAchieved	13.00%
Natural Gas Therms [Member] \| Financial [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,080,345	852,435	1,006,665
Natural Gas Therms [Member] \| Physical [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	749,838	463,254	672,350
Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, Notional Amount \| $	$ 10,483	$ 7,617	$ 9,905