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Commitments and Contingencies - Schedule of Future Minimum Rental Payments for Operating Leases (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Schedule Of Future Minimum Rental Payments For Operating Leases [Line Items]
2013	$ 2,824
2014	2,848
2015	2,864
2016	2,900
2017	2,170
Thereafter
Future minimum annual rental commitments	$ 13,606

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