Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Sep. 22, 2016	May 26, 2015
Debt Instrument [Line Items]
Total debt	$ 3,570	$ 3,569
Less: short-term debt including current maturities	400	399
Long-term debt	$ 3,170	3,170
Senior notes \| 2.5% Senior Notes, due 2018
Debt Instrument [Line Items]
Stated interest rate (as a percent)	2.50%
Long-term debt	$ 400	399
Unamortized debt discount and issuance costs (less than $1 million)	$ 1
Senior notes \| 3.3% Senior Notes, due 2020
Debt Instrument [Line Items]
Stated interest rate (as a percent)	3.30%
Long-term debt	$ 697	697
Unamortized debt discount and issuance costs (less than $1 million)	$ 3
Senior notes \| 4.0% Senior Notes, due 2025
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.00%			4.00%
Long-term debt	$ 692	692
Unamortized debt discount and issuance costs (less than $1 million)	$ 8
Senior notes \| 4.4% Senior Notes, due 2026
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.40%
Long-term debt	$ 892	892
Unamortized debt discount and issuance costs (less than $1 million)	$ 8
Senior notes \| 2.95% Senior Notes, due 2027
Debt Instrument [Line Items]
Stated interest rate (as a percent)	2.95%		2.95%
Long-term debt	$ 493	493
Unamortized debt discount and issuance costs (less than $1 million)	$ 7
Senior notes \| 6.55% Senior Notes, due 2037
Debt Instrument [Line Items]
Stated interest rate (as a percent)	6.55%
Long-term debt	$ 396	$ 396
Unamortized debt discount and issuance costs (less than $1 million)	$ 4