Commitments - Additional Information (Detail) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	May. 31, 2015 ft²	Feb. 28, 2015 ft²
Operating Leased Assets [Line Items]
Operating lease expiration year	2023
Rent expense | $	$ 1,291	$ 742	$ 549
Lease Agreements | Lease Property One
Operating Leased Assets [Line Items]
Operating lease facility area				33
Lease Agreements | Lease Property Two
Operating Leased Assets [Line Items]
Operating lease facility area					42