Income Taxes Rate Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory Federal Income Tax Rate	21.00%	21.00%	35.00%
Provision for Income Taxes at Statutory Rate	$ 855	$ 685	$ 850
Foreign rate differential	(204)	(375)	(380)
Foreign exchange loss on inter-company debt refinancing	(62)		(237)
Income tax credits	(379)	(349)	(273)
Withholding taxes	38	31	55
Global intangible low-taxed income	258	167
Foreign-derived intangible income	(111)	(47)
Impact of change in tax laws and apportionment on deferred taxes	6	(12)	(1,121)
Transition tax and other impacts of U.S. tax reform	8	117	1,250
Provision for (reversal of) tax reserves, net	62	(49)	99
Excess tax benefits from stock options and restricted stock units	(80)	(77)	(65)
Basis difference on disposal of business	73
Valuation allowance	(4)	260	7
Intra-entity transfers	(79)
Other, net	(7)	(27)	16
Provision for Income Taxes	374	324	201
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)	1	68	204
Tax Cuts And Jobs Act of 2017, Remeasurement of Deferred Taxes due to Change In Tax Rate			(1,060)
US foreign tax credits generated by repatriation of foreign earnings			86
US Income taxes on repatriated foreign earnings			53
United States
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Provision for (reversal of) tax reserves, net	(7)
Credits Generated Due To Tax Planning Initiatives, Sweden [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
US foreign tax credits generated by repatriation of foreign earnings	75		$ 20
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] \| Anatomical Pathology business [Member]
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Valuation allowance		$ 71
Income Tax Provision Related to Gain of Sale of Business	$ 191

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