Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Unrecognized Tax Benefits | |||
| Beginning balance | $ 2,661 | $ 2,852 | $ 2,701 |
| Increase due to acquisition | 2,674 | 0 | 0 |
| Increase due to current year tax positions | 91 | 113 | 163 |
| Increase due to prior year tax positions | 59 | 499 | 110 |
| Decrease due to prior year tax positions | (7) | (21) | (36) |
| Settlements | (141) | (749) | (79) |
| Lapse of statutes of limitations | (73) | (33) | (7) |
| Ending balance | 5,264 | 2,661 | 2,852 |
| Net amount of potential tax benefits that would impact the entity's effective tax rate | 5,000 | 2,400 | |
| Reimbursement receivable for unrecognized tax benefits and related interest and penalties for periods after separation | 81 | ||
| Interest and penalties | 142 | 51 | 73 |
| Accrued interest and penalties | 642 | $ 191 | $ 190 |
| Reasonably possible amount that gross unrecognized tax benefits may change within the next twelve months, high end of range | $ 68 | ||
| X | ||||||||||
- Definition Represents the amount of reimbursement receivable for unrecognized tax benefits and related interest and penalties. No definition available.
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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in unrecognized tax benefits resulting from acquisitions. No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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