Future Scheduled Principal Payments Due under Financing Obligations (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Bank Term Loan
Future scheduled principal payments under bank term loan due 2012	$ 1,050
Future scheduled principal payments under bank term loan due 2013	2,100
Future scheduled principal payments under bank term loan due 2014	4,200
Future scheduled principal payments under bank term loan due 2015	4,900
Bank term loan	12,250	12,600
Less current portion	(1,575)
Bank term loan, long-term portion	10,675
Capital Lease Obligations
Future scheduled principal payments under capital lease due 2012	39
Future scheduled principal payments under capital lease due 2013	15
Future scheduled principal payments under capital lease due 2014
Future scheduled principal payments under capital lease due 2015
Capital lease obligations	54
Less current portion	(51)
Capital leases obligations, long-term portion	$ 3

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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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.

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