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Fair Value Measurements, Derivative Instruments, Gains & Losses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Cross Currency Interest Rate Contract [Member] \| Other Expense, Net [Member] \| Derivatives Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative, Net	$ 1		$ (9)
Currency Exchange Contracts [Member] \| Cost of Product Revenues [Member] \| Derivatives Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative, Net	(2)	$ 1	(2)
Currency Exchange Contracts [Member] \| Other Expense, Net [Member] \| Derivatives Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative, Net	51	43	7	$ 49
Fair Value Hedging [Member] \| Interest Rate Swaps [Member] \| Other Expense, Net [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Hedged long-term obligations in Fair Value Hedge		(14)	(43)	(95)
Gain (Loss) on Derivative, Net		15	43	98
Cash Flow Hedging [Member] \| Interest Rate Swaps [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) in OCI on Cash Flow Hedge		(50)	(85)	(50)
Payments for Hedge, Financing Activities			85
Cash Flow Hedging [Member] \| Interest Rate Swaps [Member] \| Other Expense, Net [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Cash Flow Hedge Reclassified from AOCI	(8)	(3)	(14)	(10)
Net Investment Hedging [Member] \| Foreign currency-denominated debt [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) in Currency Translation Adjustment on Net Investment Hedge	(295)	261	(276)	320
Net Investment Hedging [Member] \| Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) in Currency Translation Adjustment on Net Investment Hedge	(30)	72	(30)	79
Net Investment Hedging [Member] \| Cross Currency Interest Rate Contract [Member] \| Other Expense, Net [Member] \| Derivatives Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative, Net	$ 2	$ 13	$ 9	$ 41