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Acquisition of Versant Health Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		$ 0	$ 2,190	$ 0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		0	315	0
Cash Acquired from Acquisition		0	191	0
Goodwill		9,535	10,112	9,308	$ 9,422
Finite-lived Intangible Assets Acquired		$ 0	$ 814	$ 0
Value Of Distribution Agreements And Value Of Customer Relationships Acquired Intangible Asset [Member] \| Maximum
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		40 years
Value Of Distribution Agreements And Value Of Customer Relationships Acquired Intangible Asset [Member] \| Minimum
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		9 years
Versant Health, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 1,800
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	323
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	95
Cash Acquired from Acquisition	189
Goodwill	890
Finite-lived Intangible Assets Acquired	790
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	115
Deferred Tax Liabilities, Tax Deferred Income	$ 217
Versant Health, Inc. [Member] \| Maximum
Business Acquisition [Line Items]
Versant Health total revenue		2.00%	2.00%	2.00%
Versant Health, Inc. [Member] \| Value Of Distribution Agreements And Value Of Customer Relationships Acquired Intangible Asset [Member] \| Maximum
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		15 years
Versant Health, Inc. [Member] \| Value Of Distribution Agreements And Value Of Customer Relationships Acquired Intangible Asset [Member] \| Minimum
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life		9 years