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Employee Postretirement Benefits - Schedule of Amounts Not Yet Recognized as Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Pension Benefits (Pension Plan) |  |
Regulatory Assets (Liabilities): |  |
Unrecognized Prior Service Cost | $ 0 | $ 0
Unrecognized Actuarial Loss | 87,868 | 85,227
Net Regulatory Assets (Liabilities) | 87,868 | 85,227
Accumulated Other Comprehensive Income (Loss): |  |
Unrecognized Prior Service Cost | 0 | 0
Unrecognized Actuarial Gain (Loss) | 1,937 | 1,994
Total Accumulated Other Comprehensive Income (Loss) | 1,937 | 1,994
Pension Benefits (ESSRP) |  |
Regulatory Assets (Liabilities): |  |
Unrecognized Prior Service Cost | 0 | 0
Unrecognized Actuarial Loss | 292 | 1,061
Net Regulatory Assets (Liabilities) | 292 | 1,061
Accumulated Other Comprehensive Income (Loss): |  |
Unrecognized Prior Service Cost | 0 | 0
Unrecognized Actuarial Gain (Loss) | (2,502) | (1,403)
Total Accumulated Other Comprehensive Income (Loss) | (2,502) | (1,403)
Postretirement Benefits |  |
Regulatory Assets (Liabilities): |  |
Unrecognized Prior Service Cost | (12,703) | (18,845)
Unrecognized Actuarial Loss | 1,121 | 1,759
Net Regulatory Assets (Liabilities) | (11,582) | (17,086)
Accumulated Other Comprehensive Income (Loss): |  |
Unrecognized Prior Service Cost | 339 | 498
Unrecognized Actuarial Gain (Loss) | 732 | 707
Total Accumulated Other Comprehensive Income (Loss) | $ 1,071 | $ 1,205

X
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- Definition Represents unrecognized actuarial net gains (losses) pertaining to regulatory assets under a defined benefit plan. + References No definition available. + Details
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- Definition Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (j) -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (k) -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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