Schedule of Future Minimum Payments Under Capitalized Leases (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Leases Future Minimum Payments [Line Items]
2013	$ 2,654
2014	2,654
2015	2,654
2016	2,654
2017	2,654
Thereafter	28,528
Total minimum capital lease payments	41,798
Less amounts representing interest	(15,930)
Present value of net minimum capital lease payments	25,868
Less current maturities of capital lease obligations	964	718
Total long-term capital lease obligations	$ 24,904	$ 21,114

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.

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