Fair Value Measurements, Derivative Assets & Liabilities (Details) - USD ($) $ in Millions	Jun. 29, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability	$ (19)	$ (93)
Long-term Obligations [Member]
Derivatives, Fair Value [Line Items]
Hedged Liability, Fair Value Hedge	3,368	3,291
Cumulative Amount of Fair Value Hedging Adjustment - Increase (Decrease) Included in Carrying Amount of Liability	(19)	(93)
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	24	30
Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	3,100	3,100
Interest Rate Swaps [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	46	129
Cross Currency Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	1,800	1,500
Cross Currency Interest Rate Contract [Member] \| Derivatives Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	36	28
Currency Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amount Of Derivatives	3,642	3,424
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	6	3
Currency Exchange Contracts [Member] \| Derivatives Not Designated as Hedging Instrument [Member] \| Other Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	20	16
Fair Value, Measurements, Recurring [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	42	31
Derivative Liabilities	$ 66	$ 145

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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