Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments And Contingencies Disclosure [Abstract]
Rental and lease expense incurred	$ 81	$ 86	$ 98
Standard product warranty description	obligate us to repair, replace or credit the purchase price of a covered product back to the buyer.

Describes the nature of the product warranty, including the approximate term of the product warranty, how the product warranty arose, and the events or circumstances that would require the warrantor to perform under the product warranty.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration