Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Other borrowings	$ 9	$ 7
Total debt	4,900	4,562
Less: current maturities	(3)	(95)
Long-term debt	4,897	4,467
Term loan
Debt Instrument [Line Items]
Long-term debt	540	629
Senior notes \| 2.7% senior notes due 2020
Debt Instrument [Line Items]
Long-term debt	$ 846	845
Interest rate	2.70%
Senior notes \| 4.625% senior notes due 2020
Debt Instrument [Line Items]
Long-term debt	$ 449	448
Interest rate	4.625%
Senior notes \| 4.75% senior notes due 2021
Debt Instrument [Line Items]
Long-term debt	$ 398	398
Interest rate	4.75%
Senior notes \| 3.5% senior notes due 2022
Debt Instrument [Line Items]
Long-term debt	$ 696	695
Interest rate	3.50%
Senior notes \| 3.85% senior notes due 2025
Debt Instrument [Line Items]
Long-term debt	$ 894	893
Interest rate	3.85%
Revolving credit facility
Debt Instrument [Line Items]
Long-term debt	$ 1,068	$ 647

Contractual interest rate for funds borrowed, under the debt agreement.

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

+ References

Reference 1: 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(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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Amount of long-term debt and capital lease obligations including current maturities.

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Amount of long-term debt classified as other.

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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