Derivatives and Hedging Instruments - Derivative Fair Values (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value	$ 3	$ 5
Derivative Liabilities, Fair Value	1	1
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value	3	4
Derivative Liabilities, Fair Value	0	0
Derivatives designated as hedging instruments \| Foreign exchange contracts \| Other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	89	169
Derivative Assets, Fair Value	3	4
Derivatives designated as hedging instruments \| Foreign exchange contracts \| Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	0
Derivative Liabilities, Fair Value	0	0
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value	0	1
Derivative Liabilities, Fair Value	1	1
Derivatives not designated as hedging instruments \| Foreign exchange contracts \| Other current assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	154	219
Derivative Assets, Fair Value	0	1
Derivatives not designated as hedging instruments \| Foreign exchange contracts \| Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	280	157
Derivative Liabilities, Fair Value	$ 1	$ 1

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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