Build-to-Suit Lease Obligation - Schedule of Expected Reductions (Increases) in Build-to-Suit Lease Obligation (Detail) $ in Thousands	Sep. 30, 2015 USD ($)
Leases [Abstract]
Build-to-Suit Lease Obligation, Remainder of 2015	$ 218
Build-to-Suit Lease Obligation, 2016	(19)
Build-to-Suit Lease Obligation, 2017	47
Build-to-Suit Lease Obligation, 2018	119
Build-to-Suit Lease Obligation, 2019	197
Build-to-Suit Lease Obligation, 2020 and after	16,578
Total minimum payments	$ 17,140