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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Defined Benefit Plan Disclosure [Line Items] |  |
Payment for pension benefits | $ 3 | $ 3
Percentage of service related net periodic benefit costs capitalized to utility property | 45.00% |
Percentage of service related net periodic benefit costs recorded to operating expenses | 55.00% |
Percentage of non-service related net periodic benefit costs capitalized to regulatory assets | 45.00% |
Percentage of non-service related net periodic benefit costs recorded to other expense | 55.00% |
Pension Plans, Defined Benefit [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Expected contributions to pension plan | $ 10 |

X
- Definition Percentage of non-service related net periodic benefit costs capitalized to regulatory assets. + References No definition available. + Details
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- Definition Percentage of non-service related net periodic benefit costs recorded to other expense. + References No definition available. + Details
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- Definition Percentage of service related net periodic benefit costs capitalized to utility property. + References No definition available. + Details
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- Definition Percentage of service related net periodic benefit costs recorded to operating expenses. + References No definition available. + Details
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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. + Details
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (g) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-25 + Details
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- Details
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