Future Scheduled Principal Payments Due under Term Loan (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Term Loan
Future scheduled principal payments under term loan due 2013	$ 1,575
Future scheduled principal payments under term loan due 2014	4,200
Future scheduled principal payments under term loan due 2015	4,900
Term loan	10,675	11,200
Less current portion	(2,625)
Term loan, long-term portion	$ 8,050

Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Carrying value as of the balance sheet date of current portion of long-term loans payable to bank due within one year or the operating cycle if longer.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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