Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio

No definition available.

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- Definition

Long-term debt, Current Maturities, Gross

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

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

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-Publisher FASB
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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

Fixed interest rate related to the interest rate derivative.

+ 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.

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- Definition

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

+ References

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

Amount of long-term debt classified as other.

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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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-Publisher FASB
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- Definition

The cash inflow from amounts received from a long-term debt instrument secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default.

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- Definition

The cash inflow from a debt funding received on a regular basis with maturities ranging from 5-10 years.

+ References

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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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.

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Long-Term Debt - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
Long-Term Debt - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Aug. 04, 2023
Debt Instrument [Line Items]
Long-term Debt	$ 1,535,302	$ 1,045,006	$ 1,336,864
Other Long-Term Debt	6,000	3,500	6,200
Unamortized debt issuance costs	10,428	8,171	8,987
Long-term Debt, Gross	1,545,730	1,053,177	1,345,851
Long-term debt, Current Maturities, Gross	240,700	300	90,700
Long-term debt	1,294,590	1,044,667	1,246,167
Northwest Natural Gas Company [Member]
Debt Instrument [Line Items]
Long-term Debt	1,324,422	986,627	1,125,877
Unamortized debt issuance costs	$ 10,278	$ 8,073	$ 8,823
Weighted average interest rate	4.60%	4.40%	4.50%
Long-term Debt, Gross	$ 1,334,700	$ 994,700	$ 1,134,700
Long-term debt	$ 1,234,460	$ 986,627	$ 1,035,935
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%
18 Month Credit Agreement Due March 15, 2024
Debt Instrument [Line Items]
Weighted average interest rate	5.40%	0.00%	4.20%
Long-term Debt, Term	18 months
Proceeds from Issuance of Debt	$ 100,000	$ 0	$ 100,000
Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio	70.00%
Derivative, Fixed Interest Rate	4.70%
18 Month Credit Agreement Due March 15, 2024 \| NWN Water
Debt Instrument [Line Items]
Weighted average interest rate	5.30%	0.00%	4.20%
Long-term Debt, Term	18 months
Proceeds from Issuance of Debt	$ 50,000	$ 0	$ 50,000
Debt Instrument Covenant Consolidated Indebtedness to Capitalization Ratio	70.00%
First Mortgage Bonds 4.8 Percent Series Due 2052 \| Northwest Natural Gas Company [Member]
Debt Instrument [Line Items]
Stated interest rate	4.80%
Proceeds from Issuance of Debt	$ 140,000
NWN Water Term Loan Due 2026
Debt Instrument [Line Items]
Derivative, Fixed Interest Rate	3.80%
NWN Water Term Loan Due 2026 \| Corporate, Non-Segment [Member] \| Other Northwest Holdings [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 55,000
NWN Water Term Loan Due 2026 \| NWN Water
Debt Instrument [Line Items]
Long-term Debt	$ 55,000	$ 55,000	$ 55,000
Weighted average interest rate	4.90%	1.20%	2.50%
Note 5430 Series Due 2053
Debt Instrument [Line Items]
Stated interest rate	5.43%
Note 5430 Series Due 2053 \| Northwest Natural Gas Company [Member]
Debt Instrument [Line Items]
Stated interest rate	5.43%
Proceeds from Issuance of First Mortgage Bond	$ 100,000
Secured Debt	$ 100,000
Note 5750 \| Northwest Natural Gas Company [Member]
Debt Instrument [Line Items]
Stated interest rate	5.75%
Proceeds from Issuance of Medium-term Notes	$ 100,000
Note 5180 due 2034 \| Forecast [Member]
Debt Instrument [Line Items]
Stated interest rate				5.18%
Note 5180 due 2034 \| Northwest Natural Gas Company [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Secured Debt				$ 80,000
Note 5230 due 2038 \| Forecast [Member]
Debt Instrument [Line Items]
Stated interest rate				5.23%
Note 5230 due 2038 \| Northwest Natural Gas Company [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Secured Debt				$ 50,000