Debt - Debt Issuances (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease obligations	$ 23	$ 26
Principal debt balance	1,579	1,598
Debt issuance costs and unamortized discounts	(30)	(31)
Less: current maturities	(53)	(55)
Total Long-term Debt	1,496	1,512
Term Loan A due 2022
Debt Instrument [Line Items]
Long-term debt, gross	691	705
Term Loan B due 2023
Debt Instrument [Line Items]
Long-term debt, gross	831	833
Senior Notes due 2024
Debt Instrument [Line Items]
Long-term debt, gross	$ 34	$ 34

Long-Term Debt, Excluding Current Maturities And Capital Lease Obligations

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- Definition

Long-Term Debt, Gross And Capital Lease Obligations

+ References

No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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-Publisher FASB
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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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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.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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