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Government Assistance (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Government Assistance [Line Items] |  |  |
Government Assistance, Liability, Statement of Financial Position [Extensible Enumeration] | Other noncurrent liabilities |  | Other noncurrent liabilities
Nuclear PTCs |  |  |
Government Assistance [Line Items] |  |  |
Estimate |  | $ 304 |
Estimated nuclear PTC receivable | $ 130 |  |
Estimated nuclear PTCs credits used | 40 |  | $ 150
Estimated refunds recognized | 1,030 |  | 1,030
Government assistance, operating income, increase (decrease) | $ (110) | $ (69) |
Nuclear PTCs | Deferred Costs and Other Assets |  |  |
Government Assistance [Line Items] |  |  |
Estimated nuclear PTC receivable |  |  | 185
Nuclear PTCs | Other Current Assets |  |  |
Government Assistance [Line Items] |  |  |
Estimated nuclear PTC receivable |  |  | $ 95

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- Definition Amount of asset from government assistance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 832 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483507/832-10-50-3 + Details
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- Definition Amount of liability from government assistance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 832 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483507/832-10-50-3 + Details
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- Definition Amount of decrease in liability from government assistance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 832 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483507/832-10-50-3 + Details
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- Definition Indicates line item in statement of financial position that includes liability from government assistance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 832 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483507/832-10-50-3 + Details
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- Definition Amount of increase (decrease) in income from government assistance, classified as operating. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 832 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483507/832-10-50-3 + Details
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