Dispositions (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 28, 2019	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business				$ 505	$ 0
Revenues		$ 6,316	$ 6,078	12,441	$ 11,931
Current Assets		11,223		11,223		$ 10,625
Current Liabilities		$ 7,509		7,509		6,147
Anatomical Pathology business [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Consideration	$ 1,130
Gain (Loss) on Disposition of Business	$ 505
Revenues				$ 115		238
Current Assets						81
Long-term Assets						528
Current Liabilities						34
Long-term Liabilities						$ 24