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Benefit Plans and Other Postretirement Benefits - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) benefitPlan | Dec. 31, 2021 USD ($)
Benefit Plans and Other Postretirement Benefits |  |
Number of qualified pension plans | benefitPlan | 3 |
Pension Benefits |  |
Benefit Plans and Other Postretirement Benefits |  |
Expects to contribute to the pension plans | $ 83 |
Actuarial gain | 289 | $ 55
Pension Benefits | GenOn |  |
Benefit Plans and Other Postretirement Benefits |  |
Expects to contribute to the pension plans | $ 45 |

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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 + Details
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- Details
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- Details
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