Other Liabilities - Long-Term Table (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
VPP deferred revenue(a)	$ 49	$ 63
Unrecognized tax benefits	53	53
Other	108	103
Total other long-term liabilities	$ 210	$ 219

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting, and liabilities classified as noncurrent and other.

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Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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