Derivatives - BS Location (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	$ 142	$ 146
Fair Value of Derivative Instruments, Liabilities	20	53
Derivatives designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	131	132
Fair Value of Derivative Instruments, Liabilities	12	47
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	64	74
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	50	39
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	9	12
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	3	4
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	1,995	2,277
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Noncurrent balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	1,041	1,099
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	17	19
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities		14
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities		17
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	500	1,000
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Noncurrent balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	603	1,403
Derivatives not designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	11	14
Fair Value of Derivative Instruments, Liabilities	8	6
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	11	14
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	8	6
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Current balance sheet location
Location and Fair Value Amount of Derivative Instruments
Derivative Notional Amount	$ 2,684	$ 2,484

Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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