Environmental Matters - Regulatory Assets (Details) - USD ($) $ in Thousands |
6 Months Ended | ||
|---|---|---|---|
Jun. 30, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
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| Site Contingency [Line Items] | |||
| Current regulatory assets | $ 168,092 | $ 143,745 | $ 103,914 |
| Long-term regulatory assets | $ 640,656 | $ 424,194 | $ 372,668 |
| Remediation non-recovery Percentage | 3.30% | 3.30% | 3.30% |
| Annual tariff rider collection | $ 5,000 | ||
| Oregon | |||
| Site Contingency [Line Items] | |||
| Remediation recovery percentage | 96.70% | ||
| NW Natural | |||
| Site Contingency [Line Items] | |||
| Current regulatory assets | $ 167,442 | $ 143,135 | $ 103,190 |
| Long-term regulatory assets | 633,188 | 419,847 | 370,536 |
| NW Natural | Environmental costs | |||
| Site Contingency [Line Items] | |||
| Deferred costs and interest | 79,609 | 71,954 | 69,335 |
| Accrued site liabilities | 362,225 | 161,993 | 150,488 |
| Insurance proceeds and interest | (42,851) | (41,736) | (48,257) |
| Total regulatory asset deferral | 398,983 | 192,211 | 171,566 |
| Current regulatory assets | 12,690 | 12,148 | 11,447 |
| Long-term regulatory assets | $ 386,293 | $ 180,063 | $ 160,120 |
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- Definition Annual Tariff rider collection No definition available.
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- Definition Environmental Regulatory Insurance Proceeds And Interest No definition available.
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- Definition Regulatory Assets, Environmental Regulatory Accrued Site Liabilities No definition available.
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- Definition Regulatory Assets, Environmental Regulatory Deferred Cost And Interest No definition available.
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- Definition Remediation Non-Recovery Percentage No definition available.
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- Definition Remediation Recovery Percentage No definition available.
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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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