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v3.25.1

Fair Value of Financial Assets and Liabilities - Fair Value Reconciliation of Level 3 Assets and Liabilities Measured on a Recurring Basis (Details) - Level 3 - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning Balance | $ 502 | $ 1,299
Total realized / unrealized gains (losses) |  |
Included in net income (loss) | (130) | (306)
Included in Payable related to Regulatory Agreement Units |  | 3
Change in collateral | 67 | 33
Purchases, sales, issuances and settlements |  |
Purchases | 15 | 37
Sales | (3) | (44)
Settlements | (2) | (7)
Transfers into Level 3 | 0 | 9
Transfers out of Level 3 | 36 | (45)
Ending Balance | 485 | 979
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities | (95) | 29
NDT Fund Investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning Balance | 502 | 429
Total realized / unrealized gains (losses) |  |
Included in net income (loss) | 1 | 0
Included in Payable related to Regulatory Agreement Units |  | 3
Change in collateral | 0 | 0
Purchases, sales, issuances and settlements |  |
Purchases | 0 | 33
Sales | 0 | 0
Settlements | (2) | (5)
Transfers into Level 3 | 1 | 0
Transfers out of Level 3 | 0 | 0
Ending Balance | 502 | 460
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities | 1 | 0
Mark-to-Market Derivatives |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning Balance | (1) | 869
Total realized / unrealized gains (losses) |  |
Included in net income (loss) | (131) | (306)
Included in Payable related to Regulatory Agreement Units |  | 0
Change in collateral | 67 | 33
Purchases, sales, issuances and settlements |  |
Purchases | 15 | 4
Sales | (3) | (44)
Settlements | 0 | (2)
Transfers into Level 3 | (1) | 9
Transfers out of Level 3 | 36 | (45)
Ending Balance | (18) | 518
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities | (96) | 29
Footnotes To Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Abstract] |  |
Realized gains (losses) | (35) | (337)
Rabbi trust investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning Balance | 1 | 1
Total realized / unrealized gains (losses) |  |
Included in net income (loss) | 0 | 0
Included in Payable related to Regulatory Agreement Units |  | 0
Change in collateral | 0 | 0
Purchases, sales, issuances and settlements |  |
Purchases | 0 | 0
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Ending Balance | 1 | 1
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities | $ 0 | $ 0

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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis, Gain (Loss) Included In Noncurrent Payables To Affiliates + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from asset and liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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