Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of income before income taxes

Income Before Income Taxes
Year ended December 31 (in millions)	2021		2020		2019
Domestic	$	21,243	$	16,211	$	16,646
Foreign	(2,150)		(2,146)		350
	$	19,093	$	14,065	$	16,996

Schedule for the components of income tax expense

Components of Income Tax Expense
Year ended December 31 (in millions)	2021		2020		2019
Current (Expense) Benefit:
Federal	$	(2,355)	$	(2,824)	$	(2,085)
State	(669)		(836)		(425)
Foreign	(343)		(254)		(600)
	(3,367)		(3,914)		(3,110)
Deferred (Expense) Benefit:
Federal	(1,504)		111		(902)
State	(255)		71		15
Foreign	(133)		368		324
	(1,892)		550		(563)
Income tax (expense) benefit	$	(5,259)	$	(3,364)	$	(3,673)

Schedule of items that effect income tax expense

Our income tax expense differs from the federal statutory amount because of the effect of the items detailed in the table below. 

Year ended December 31 (in millions)	2021		2020		2019
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)

Schedule of the components of net deferred tax liability

Components of Net Deferred Tax Liability
December 31 (in millions)	2021		2020
Deferred Tax Assets:
Net operating loss and other loss carryforwards	$	3,194	$	2,609
Nondeductible accruals and other	3,246		3,253
Less: Valuation allowance	2,907		2,312
	3,533		3,550
Deferred Tax Liabilities:
Differences between book and tax basis of property and equipment and intangible assets	30,584		29,829
Differences between book and tax basis of investments	526		405
Differences between book and tax basis of long-term debt	1,788		680
Differences between book and tax basis of foreign subsidiaries and undistributed foreign earnings	394		468
	33,292		31,382
Net deferred tax liability	$	29,759	$	27,832

Schedule of changes in the valuation allowance for deferred tax assets

The following table presents changes in our valuation allowance for deferred tax assets:

(in millions)	2021		2020		2019
Beginning balance	$	2,312	$	1,906	$	632
Additions charged to income tax expense and other accounts	635		430		1,403
Deductions from reserves	40		24		129
Ending balance	$	2,907	$	2,312	$	1,906

Reconciliation of unrecognized tax benefits

Reconciliation of Unrecognized Tax Benefits
(in millions)	2021		2020		2019
Gross unrecognized tax benefits, January 1	$	1,879	$	1,422	$	1,543
Additions based on tax positions related to the current year	352		436		230
Additions based on tax positions related to prior years	111		152		133
Reductions for tax positions of prior years	(181)		(31)		(344)
Reductions due to expiration of statutes of limitations	(107)		(76)		(117)
Settlements with tax authorities and other	(12)		(24)		(23)
Gross unrecognized tax benefits, December 31	$	2,042	$	1,879	$	1,422