Income Taxes - Federal Statutory (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal tax at statutory rate	$ (4,009)	$ (2,954)	$ (3,569)
State income taxes, net of federal benefit	(464)	(265)	(306)
Foreign income taxed at different rates	(392)	(24)	(126)
Adjustments to uncertain and effectively settled tax positions, net	(238)	(344)	(3)
Federal research and development credits	85	164	124
Excess tax benefits recognized on share-based compensation	209	150	196
Tax legislation	(498)	(120)	31
Other	48	29	(20)
Income tax (expense) benefit	$ (5,259)	$ (3,364)	$ (3,673)

Effective Income Tax Rate Reconciliation, Adjustments To Uncertain And Effective Settled Tax Positions, Net, Amount

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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