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 entity's net deferred tax assets and liabilities (federal and state) pertaining to continuing operations.

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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.

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The net amount of change in unrecognized tax benefits resulting from settlements with taxing authorities.

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The tax impact of reconciling items included in Unrecognized Tax Benefits.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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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.

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