v3.20.4

Income Taxes (Changes In Unrecognized Tax Benefits Balance For Federal State And Foreign Tax) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |
Balance at beginning of year | $ 10,979 | $ 10,358
Increases for tax positions related to the current year | 1,580 | 903
Increases for tax positions related to prior years | 112 | 1,106
Decreases for tax positions related to prior years | (994) | (1,283)
Lapse of statute of limitations | (24) | (32)
Settlements | (1,646) | (283)
Current year acquisitions | 0 | 205
Foreign currency effects | (6) | 5
Balance at end of year | 10,001 | 10,979
Accrued interest and penalties | 2,450 | 2,708
Gross unrecognized income tax benefits | 12,451 | 13,687
Less: Deferred federal and state income tax benefits | (878) | (886)
Less: Tax attributable to timing items included above | (3,588) | (4,320)
Total UTB that, if recognized, would impact the effective income tax rate as of the end of the year | $ 7,985 | $ 8,481

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- Definition The gross amount of unrecognized tax benefits (tax reductions recognized in financial reports but excluded from tax returns) pertaining to uncertain tax positions taken in tax returns as of the beginning balance sheet date, excluding amounts pertaining to deferred income tax benefits and timing. + References No definition available. + Details
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- Definition Unrecognized Tax Benefits, Increase (Decrease) Resulting From Foreign Currency Translation + References No definition available. + Details
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