v3.20.4

Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Operating Loss Carryforwards [Line Items] |  |  |
Net operating and capital loss carryforwards (tax effected) for federal income tax purposes | $ 585 |  |
Net operating and capital loss carryforwards (tax effected) for state income tax purposes | 916 |  |
Net operating and capital loss carryforwards (tax effected) for foreign income tax purposes | 2,763 |  |
Amount of deposits that reduced UTB balance | 702 | $ 2,584 |
Accrued interest and penalties included in unrecognized tax benefits balance at year end | 2,450 | 2,708 |
Net interest and penalty expense included in income tax expense | 149 | $ 267 | $ 1,290
Federal |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Tax credit carryforwards | 1,080 |  |
State |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Tax credit carryforwards | $ 2,011 |  |

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