Income Taxes Rate Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory federal income tax rate	21.00%	21.00%	21.00%
Provision for income taxes at statutory rate	$ 1,857	$ 1,518	$ 855
Foreign rate differential	(255)	(223)	(204)
Income tax credits	(315)	(335)	(213)
Global intangible low-taxed income	76	86	92
Foreign-derived intangible income	(119)	(156)	(111)
Excess tax benefits from stock options and restricted stock units	(124)	(114)	(80)
Provision for (reversal of) tax reserves, net	(17)	(26)	62
Intra-entity transfers	(284)		(79)
Foreign exchange loss on inter-company debt refinancing		(47)	(62)
Domestication transaction		(263)
Valuation allowance	36	379	(4)
Withholding taxes	164	115	38
Basis difference on disposal of business		0	73
Tax return reassessments and settlements	1	(196)	(6)
State income taxes, net of federal tax	82	147	22
Other, net	7	(35)	(9)
Provision for income taxes	1,109	850	374
US foreign tax credits generated by repatriation of foreign earnings		96	75
Deferred Tax Implications
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Intra-entity transfers	188
Capital Loss
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Intra-entity transfers	$ 96
Deferred Tax Asset, Interest Carryforward [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Valuation allowance		212
United States
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Provision for (reversal of) tax reserves, net		(378)
Valuation allowance		156
Tax return reassessments and settlements		(25)
Unrecognized tax benefits reclassed to accrued income taxes in connection with IRS settlement		144
Charge for Expired Tax Credits due to Audit Settlement		$ 53
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] \| Anatomical Pathology business [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income Tax Provision Related to Gain of Sale of Business			$ 191

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