Long Term Debt (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Long-Term Obligations	$ 102,700,000	$ 145,400,000
Current portion of long-term obligations	(35,807,000)	(33,888,000)
Total	66,904,000	111,551,000
Series A Notes
Debt Instrument [Line Items]
Senior Notes	20,000,000	35,000,000
Series B Notes
Debt Instrument [Line Items]
Senior Notes	20,000,000	30,000,000
Series C Notes
Debt Instrument [Line Items]
Senior Notes		35,000,000
Term Loan
Debt Instrument [Line Items]
Senior Notes		37,500,000
Term A Loan
Debt Instrument [Line Items]
Senior Notes	57,000,000
Promissory Notes
Debt Instrument [Line Items]
Promissory notes	$ 5,700,000	$ 7,900,000

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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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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, the carrying value of notes payable which were initially due after one year or beyond the normal operating cycle, if longer, and which are not otherwise defined in the taxonomy.

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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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