Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Pre-tax income	$ (887,000)	$ 8,643,000	$ 6,206,000	$ (72,000)	$ 13,630,000	$ 11,144,000	$ 6,133,000	$ 3,632,000		$ 13,890,000	$ 34,539,000	$ (14,001,000)
Excludable expenses included in pre-tax loss										9,299,000	6,169,000	28,031,000
Pre-tax income (loss)										$ 4,591,000	$ 28,370,000	$ 14,030,000
Effective tax rate excluding private placement warrants expenses										(8.50%)	38.10%	33.90%
Federal research tax credit												$ 641,000	$ 413,000
Tax credit carry forward expiration period										20 years
Scenario, Forecast [Member]
Income Taxes [Line Items]
Possible decrease in unrecognized tax benefits									$ 141,000