Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio

No definition available.

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13)(2))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Balance Type:	credit
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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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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Debt Short-term Debt - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Debt Short-term Debt - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Short-term Debt [Line Items]
Short-term debt		$ 223,000	$ 149,100	$ 65,580
Ratio of Indebtedness to Net Capital		0.580
Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Short-term debt		$ 150,000	$ 125,100	$ 45,500
Commercial Paper		$ 0
Ratio of Indebtedness to Net Capital		0.570
Line of Credit [Member]
Short-term Debt [Line Items]
Short-term debt		$ 73,000
364-Day Term Loan, Due 2021 [Member]
Short-term Debt [Line Items]
Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio		70.00%
364-Day Term Loan, Due 2021 [Member] \| Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Proceeds from Issuance of Debt		$ 150,000
364-Day Term Loan, Due 2021 [Member] \| Northwest Natural Gas Company [Member] \| Subsequent Event [Member]
Short-term Debt [Line Items]
Repayments of Debt	$ 150,000
Commercial Paper [Member]
Short-term Debt [Line Items]
Debt, Weighted Average Interest Rate		0.89%
Commercial Paper [Member] \| Northwest Natural Gas Company [Member]
Short-term Debt [Line Items]
Debt, Weighted Average Interest Rate		0.75%