Derivative Instruments (Income Statement Location) (Details) - Foreign Exchange Contract - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Foreign Currency Transaction Gain (Loss), before Tax	$ (1)	$ (5)
Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Foreign Currency Transaction Gain (Loss), before Tax	1	$ (5)
Other income (expense), net
Derivative Instruments, Gain (Loss) [Line Items]
Foreign Currency Transaction Gain (Loss), before Tax	$ (2)

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration