Dispositions (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Jun. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business				$ 0	$ 486
Revenues	$ 8,521	$ 6,272		$ 21,668	18,713
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					$ 482
Revenues			$ 115