Debt and Interest Expense - Scheduled Maturities Table (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Maturities of Long-term Debt and Capital Lease Obligations [Abstract]
2014	$ 775
2015	0
2016	1,750
2017	2,000
2018	$ 364

Amount of long-term debt and capital lease obligation maturing in the fifth fiscal year following the latest fiscal year.

No definition available.

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Amount of long-term debt and capital lease obligation maturing in the fourth fiscal year following the latest fiscal year.

No definition available.

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Amount of long-term debt and capital lease obligation maturing in the third fiscal year following the latest fiscal year.

No definition available.

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Amount of long-term debt and capital lease obligation maturing in the second fiscal year following the latest fiscal year.

No definition available.

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Amount of long-term debt and capital lease obligation maturing in the next fiscal year following the latest fiscal year.

No definition available.

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