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Inventories (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Inventories (Details) - USD ($) $ in Millions	Oct. 02, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020	Jul. 03, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw Materials	$ 1,840		$ 1,840			$ 1,305
Work in Process	680		680			540
Finished Goods	2,386		2,386			2,184
Inventories	4,906		4,906			4,029
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	4,906		4,906			$ 4,029
Product [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of revenues	(3,298)	$ (3,001)	(9,977)	$ (7,732)
Change in Accounting Principle, Other
Inventory Disclosure [Abstract]
Inventories	33		33
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	33		33
Percentage of LIFO Inventory					5.00%
Change in Accounting Principle, Other \| Laboratory Products and Services [Member]
Inventory Disclosure [Abstract]
Inventories	20		20
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	20		20
Change in Accounting Principle, Other \| Specialty Diagnostics [Member]
Inventory Disclosure [Abstract]
Inventories	13		13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	13		$ 13
Change in Accounting Principle, Other \| Product [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of revenues	33
Change in Accounting Principle, Other \| Product [Member] \| Laboratory Products and Services [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of revenues	20
Change in Accounting Principle, Other \| Product [Member] \| Specialty Diagnostics [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of revenues	$ 13