Debt Facilities - Summary of Maturities of Debt Facilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Debt Instrument [Line Items]
2013	$ 52,156
2014	449,931
2015	53,945
2016	366,684
2017	26,972
Thereafter	1,500,000
Total long term debt	$ 2,449,688

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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