Fair Value Measurements, Derivative Assets & Liabilities (Details) - USD ($) $ in Millions	Sep. 26, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability	$ 30	$ (13)
Long-term Obligations [Member]
Derivatives, Fair Value [Line Items]
Hedged Liability, Fair Value Hedge	1,024	980
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability	30	(13)
Interest Rate Swaps [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	30
Interest Rate Swaps [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		13
Interest Rate Swaps [Member] \| Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	1,000	1,000
Cross Currency Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	1,000
Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	9	33
Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	5
Cross Currency Interest Rate Contract [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	9
Cross Currency Interest Rate Contract [Member] \| Net Investment Hedging [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	900	900
Currency Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	3,893	2,846
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	10	4
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	54	11
Fair Value, Recurring [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	49	37
Derivative Liabilities	$ 68	$ 24

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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