Debt - Debt Issuances (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ (53)	$ (56)
Current maturities	(81)	(82)
Long-term debt	1,972	1,979
Term Loan A due 2021 [Member]
Debt Instrument [Line Items]
Long term debt, net of translation	728	732
Term Loan B due 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	840	842
Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	510	510
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	28	33
Long-term Debt, Parent [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 2,106	$ 2,117

Long term debt, net of translation

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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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.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

+ Details

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

+ Details

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- Definition

Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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