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Income Taxes - Reconciliation of Change in Unrecognized Tax Benefits (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Gross Unrecognized Tax Benefits |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | $ 405 | $ 451 | $ 431
Additions for tax positions related to the current year | 3 |  | 33
Additions for tax positions related to prior years | 14 | 1 | 3
Reductions for tax positions related to prior years due to IRS and other settlements | (381) | (47) | (16)
Ending balance | 41 | 405 | 451
Portion of balance at December 31, that, if recognized, would impact the effective income tax rate | 32 |  |
Accrued Interest and Penalties |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | 14 | 46 | 31
Additions for tax positions related to the current year | 0 |  | 0
Additions for tax positions related to prior years | 6 | 4 | 21
Reductions for tax positions related to prior years due to IRS and other settlements | (10) | (36) | (6)
Ending balance | 10 | 14 | 46
Portion of balance at December 31, that, if recognized, would impact the effective income tax rate | 8 |  |
Gross Tax, Interest and Penalties |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Beginning balance | 419 | 497 | 462
Additions for tax positions related to the current year | 3 |  | 33
Additions for tax positions related to prior years | 20 | 5 | 24
Reductions for tax positions related to prior years due to IRS and other settlements | (391) | (83) | (22)
Ending balance | 51 | $ 419 | $ 497
Portion of balance at December 31, that, if recognized, would impact the effective income tax rate | $ 40 |  |

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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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI https://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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