Debt Total Debt (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Total debt	$ 5,263	$ 5,010
Unamortized issuance costs	(40)	(46)
Current maturities	(503)	(504)
Debt, Net of Current Maturities and Unamortized Issuance Costs	$ 4,720	$ 4,460

Amount of short-term and long-term debt and lease obligation.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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