Fair Value of Financial Assets and Liabilities - Recurring (Details) - Fair Value, Measurements, Recurring [Member] - Significant Other Observable Inputs (Level 2) [Member] - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Assets
Deferred compensation investments in mutual funds	$ 16	$ 16
Total	26	31
Liabilities
Deferred compensation plan liabilities	17	16
Total	20	20
Foreign Exchange Forward [Member]
Assets
Foreign currency contracts - assets	10	14
Liabilities
Foreign currency contracts - liabilities	2	1
Foreign currency options [Member]
Assets
Foreign currency contracts - assets	0	1
Interest Rate Swap [Member]
Liabilities
Interest rate swaps	$ 1	$ 3

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- References

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value of financial and nonfinancial obligations.

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- Definition

Fair value portion of liability related to investment contracts for example, but not limited to, guaranteed investment contract or annuities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6487514&loc=d3e32427-158581

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