Summary of Company's Credit Facilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Senior Unsecured Notes	$ 125,000	$ 137,000
Capital Lease Obligation:
Other Debt	3,250	3,250
Credit Facilities	141,528	153,789
Related Party
Capital Lease Obligation:
Capital Lease Obligation	6,122	6,730
All Other
Capital Lease Obligation:
Capital Lease Obligation	$ 7,156	$ 6,809

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.

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

-Publisher SEC

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-Paragraph 16

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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