Long-Term Debt - Schedule of Fair Value of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Total debt at par value	$ 8,539	$ 7,112
Unamortized discount and debt issuance cost, net	(99)	(104)
Net carrying amount	8,440	7,008
Fair value	$ 8,700	$ 7,300

No definition available.

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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

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

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- Definition

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

+ References

No definition available.

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