Schedule of Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Long-term debt current and noncurrent	$ 106,742	$ 94,650
Less current portion of long-term debt	1,500	3,000
Long-term debt	105,242	91,650
Term Loan
Debt Instrument [Line Items]
Long-term debt current and noncurrent	20,000	40,000
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt current and noncurrent	64,350	29,350
Convertible Promissory Notes
Debt Instrument [Line Items]
Long-term debt current and noncurrent	20,000	20,000
Swing Loan Credit Facility
Debt Instrument [Line Items]
Long-term debt current and noncurrent	$ 2,392	$ 5,300