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Asset Retirement Obligations and Accrued Environmental Costs (Tables) | 6 Months Ended
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Jun. 30, 2025
Asset Retirement Obligation Disclosure [Abstract] |
Schedule of Asset Retirement Obligations and Accrued Environmental Costs |
|  | June 30, 2025 |  | December 31, 2024
Asset retirement obligations |  | $ | 511 |  |  | $ | 498 |
Accrued environmental costs |  | 21 |  |  | 21 |
Total asset retirement obligations and accrued environmental costs |  | 532 |  |  | 519 |
Less: asset retirement obligations and accrued environmental costs due within one year (a) |  | 54 |  |  | 51 |
Asset retirement obligations and accrued environmental costs due after one year |  | $ | 478 |  |  | $ | 468 |
__________________ (a)Presented as “Other current liabilities” on the Consolidated Balance Sheets.
Schedule of Changes in Asset Retirement Obligations | The changes of the ARO carrying value during the period were:
December 31, 2024 |  | $ | 498 |
Obligations settled |  | (12) |
Changes in estimates and (or) settlement dates |  | (3) |
Accretion expense |  | 28 |
June 30, 2025 |  | $ | 511 |
Schedule of Disaggregation of Asset Retirement Obligations | The disaggregation of ARO carrying values on the Consolidated Balance Sheets were:
|  | June 30, 2025 |  | December 31, 2024
Supplemental Information |  |  |  |
Nuclear (a) |  | $ | 257 |  |  | $ | 242 |
Non-nuclear (b) |  | 254 |  |  | 256 |
Carrying value |  | $ | 511 |  |  | $ | 498 |
__________________ (a)Obligations are expected to be settled with available funds in the NDT at the time of decommissioning. See Note 11 for additional information on the NDT. (b)Certain obligations are: (i) partially supported by surety bonds, some of which have been collateralized with LCs; or (ii) partially prefunded under phased installment agreements.

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- Definition Tabular disclosure of the carrying amount of a liability for asset retirement obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 + Details
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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 + Details
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