Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ 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

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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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

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

+ Details

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Long-Term Debt - USD ($)	3 Months Ended		6 Months Ended
Long-Term Debt - USD ($)	Sep. 30, 2021	Sep. 30, 2019	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Debt Instrument [Line Items]
Long-term Debt			$ 1,045,881,000	$ 1,044,932,000	$ 975,775,000
Unamortized debt issuance costs			$ 8,031,000	8,309,000	7,446,000
Ratio of Indebtedness to Net Capital			0.527
Northwest Natural Gas Company [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 986,762,000	986,495,000	917,409,000
Unamortized debt issuance costs			$ 7,938,000	$ 8,205,000	$ 7,291,000
Weighted average interest rate			4.40%
Long-Term Debt, Maturity, Year One			$ 0
Northwest Natural Gas Company [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Stated interest rate			2.80%
Northwest Natural Gas Company [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate			7.90%
Two-year Term Loan Due 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Term			2 years
Repayments of Debt	$ 35,000,000
Proceeds from Issuance of Debt		$ 35,000,000
Five-year Term Loan Due 2026
Debt Instrument [Line Items]
Stated interest rate			2.30%
Long-term Debt, Term			5 years
Proceeds from Issuance of Debt			$ 55,000,000
Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio			70.00%