Acquisition, Equity-Method Investment and Licensing Arrangements - Equity Method Investment Narrative (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended			6 Months Ended
		Jun. 28, 2020	Jun. 28, 2020	Sep. 29, 2019	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019	Dec. 31, 2019	Jul. 31, 2019
Schedule of Equity Method Investments [Line Items]
Gain on completion of Consumer Healthcare JV transaction	[1]		$ 0		$ 0	$ 6	$ 0
Equity-method investments	[2]	$ 15,578	15,578			15,578		$ 17,133
GSK Consumer Healthcare [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage									32.00%
Gain on completion of Consumer Healthcare JV transaction				$ 8,100
Gain on completion of Consumer Healthcare JV transaction, after-tax				$ 5,400
Equity-method investments		15,400	15,400			15,400		17,000
Equity method investment earnings			129			140
Fair value of equity method investment									$ 15,700
Underlying equity in net assets								11,000	11,200
Difference between carrying amount and underlying equity								$ 4,800	$ 4,500
Decrease due to foreign currency translation						1,100
Dividend received		$ 519
GSK [Member] | GSK Consumer Healthcare [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage									68.00%
OID [Member] | GSK Consumer Healthcare [Member]
Schedule of Equity Method Investments [Line Items]
Excess basis amortization			$ 4			$ 48
Consumer Healthcare [Member] | Held-for-sale [Member]
Schedule of Equity Method Investments [Line Items]
Pre-tax income attributable to disposal group					$ 274		$ 554
Minimum [Member] | GSK Consumer Healthcare [Member]
Schedule of Equity Method Investments [Line Items]
Excess basis amortization period						6 years
Maximum [Member] | GSK Consumer Healthcare [Member]
Schedule of Equity Method Investments [Line Items]
Excess basis amortization period						20 years

[1] Amounts may not add due to rounding.

[2] Amounts may not add due to rounding.