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Nature of Operations and Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Oct. 02, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials		$ 2,405	$ 1,922
Work in process		660	676
Finished goods		2,569	2,453
Inventories		5,634	5,051
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories		5,634	5,051
Product revenues
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of goods and services sold		$ (14,247)	$ (13,594)	$ (11,407)
Change in Accounting Principle, Other
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Inventories	$ 33
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of LIFO inventory					5.00%
Inventories	33
Change in Accounting Principle, Other \| Product revenues
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of goods and services sold	33
Change in Accounting Principle, Other \| Laboratory Products and Biopharma Services
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Inventories	20
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	20
Change in Accounting Principle, Other \| Laboratory Products and Biopharma Services \| Product revenues
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of goods and services sold	20
Change in Accounting Principle, Other \| Specialty Diagnostics
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Inventories	13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Inventories	13
Change in Accounting Principle, Other \| Specialty Diagnostics \| Product revenues
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of goods and services sold	$ 13