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Fair Value Measurements, Derivative Instruments, Gains & Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized losses on hedging instruments, net of tax	$ (62)	$ 0
Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount Of Derivatives	1,000
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	(10)
Currency Exchange Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount Of Derivatives	6,109		$ 2,846
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	3	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	40	17
Fair Value Hedging [Member] \| Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount Of Derivatives	1,000		1,000
Fair Value 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 Hedged Debt in Fair Value Hedge	(36)	(28)
Gain (Loss) on Derivative, Net	36	29
Cash Flow Hedging [Member] \| Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount Of Derivatives	750
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	(81)	0
Payments for Hedge, Financing Activities	62
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	(2)	(3)
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	83	156
Net Investment Hedging [Member] \| Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount Of Derivatives	900		$ 900
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	9	37
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	$ 5	$ 14