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Amount, after accumulated amortization, of debt discount.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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No definition available.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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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.

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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt (Details) - USD ($) $ in Millions	Oct. 20, 2016	Dec. 31, 2016	Sep. 22, 2016	Dec. 31, 2015	Aug. 18, 2015	May 26, 2015
Debt Instrument [Line Items]
Total debt		$ 3,564		$ 3,611
Less: short-term debt including current maturities		0		143
Long-term debt		3,564		3,468
Commercial Paper
Debt Instrument [Line Items]
Short-term debt		0		143
Senior Notes \| 5.9% Senior Notes, due 2017
Debt Instrument [Line Items]
Senior notes		$ 0		399
Early repayment of senior debt	$ 400
Interest rate	5.90%	5.90%
Unamortized debt discount and issuance costs		$ 2
Senior Notes \| 2.5% Senior Notes, due 2018
Debt Instrument [Line Items]
Senior notes		$ 398		398
Interest rate		2.50%			2.50%
Senior Notes \| 3.3% Senior Notes, due 2020
Debt Instrument [Line Items]
Senior notes		$ 696		695
Interest rate		3.30%			3.30%
Unamortized debt discount and issuance costs		$ 4
Senior Notes \| 4.0% Senior Notes, due 2025
Debt Instrument [Line Items]
Senior notes		$ 691		690
Interest rate		4.00%				4.00%
Unamortized debt discount and issuance costs		$ 9
Senior Notes \| 4.4% Senior Notes, due 2026
Debt Instrument [Line Items]
Senior notes		$ 891		890
Interest rate		4.40%			4.40%
Unamortized debt discount and issuance costs		$ 9
Senior Notes \| 2.95% Senior Notes, due 2027
Debt Instrument [Line Items]
Senior notes		$ 492		0
Interest rate		2.95%	2.95%
Unamortized debt discount and issuance costs		$ 8
Senior Notes \| 6.55% Senior Notes, due 2037
Debt Instrument [Line Items]
Senior notes		$ 396		$ 396
Interest rate		6.55%
Unamortized debt discount and issuance costs		$ 4