Debt Facilities (Summary of Maturities of Debt Facilities) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012
Debt Instrument [Line Items]
2012 (six months remaining)	$ 38,036
2013	69,481
2014	466,941
2015	35,819
2016	305,596
Thereafter	1,500,000
Long-term Debt, Total	$ 2,415,873

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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