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Income Taxes - Reconciliation of Change in Unrecognized Tax Benefits (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Gross Unrecognized Tax Benefits |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | $ 33 | $ 41 | $ 405
Additions for tax positions related to the current year | 12 | 2 | 3
Additions for tax positions related to prior years | 28 | 10 | 14
Reductions for tax positions related to prior years due to IRS and other settlements | (8) | (20) | (381)
Ending balance | 65 | 33 | 41
Portion of balance that if recognized, would impact the effective income tax rate | 60 |  |
Accrued Interest and Penalties |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | 7 | 10 | 14
Additions for tax positions related to the current year | 0 | 0 | 0
Additions for tax positions related to prior years | 5 | 4 | 6
Reductions for tax positions related to prior years due to IRS and other settlements | (1) | (7) | (10)
Ending balance | 11 | 7 | 10
Portion of balance that if recognized, would impact the effective income tax rate | 9 |  |
Gross Tax, Interest and Penalties |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | 40 | 51 | 419
Additions for tax positions related to the current year | 12 | 2 | 3
Additions for tax positions related to prior years | 33 | 14 | 20
Reductions for tax positions related to prior years due to IRS and other settlements | (9) | (27) | (391)
Ending balance | 76 | $ 40 | $ 51
Portion of balance that if recognized, would impact the effective income tax rate | $ 69 |  |

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 217 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-217 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10B -Publisher FASB -URI https://asc.fasb.org/1943274/2147482525/740-10-45-10B + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 217 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-217 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 15A -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-15A + Details
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