Income Taxes - Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Loss carryforwards U.S. - Federal/States	$ 228	$ 245
Loss carryforwards - Foreign	2,417	3,876
Accrued liabilities, reserves, and other expenses	2,821	2,457
Stock-based compensation	2,738	2,033
Depreciation and amortization	941	1,886
Operating lease liabilities	15,399	10,183
Other items	603	559
Tax credits	626	207
Total gross deferred tax assets	25,773	21,446
Less valuation allowance	(3,596)	(5,803)
Deferred tax assets, net of valuation allowances	22,177	15,643
Deferred tax liabilities:
Depreciation and amortization	(3,562)	(5,508)
Operating lease assets	(14,422)	(9,539)
Assets held for investment	(4,019)	(569)
Other items	(668)	(893)
Net deferred tax assets (liabilities), net of valuation allowances	$ (494)	$ (866)