Stock Incentive Plans - Summary of Non-vested Options (Detail) - $ / shares	1 Months Ended		3 Months Ended	4 Months Ended	5 Months Ended	7 Months Ended		12 Months Ended
	Sep. 30, 2014	Oct. 31, 2013	Dec. 31, 2014	Dec. 31, 2015	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Options
Options, Granted	300,000	14,450	235,650	900,084	92,600	39,300	82,815	992,684	574,950	97,265
Weighted-average exercise price
Weighted-average exercise price, Granted								$ 1.40	$ 5.04	$ 8.43
Weighted-average exercise price, Cancelled								$ 10.02	$ 16.72	$ 18.31
Non-vested Options [Member]
Options
Options, Non-vested, Beginning balance						326,566	821,002	628,733	326,566	821,002
Options, Granted								992,684	574,950	97,265
Options, Vested								(200,402)	(169,361)	(380,413)
Options, Cancelled								(169,054)	(103,422)	(211,288)
Options, Non-vested, Ending balance			628,733	1,251,961				1,251,961	628,733	326,566
Weighted-average exercise price
Weighted-average exercise price, Beginning balance						$ 13.57	$ 15.24	$ 5.93	$ 13.57	$ 15.24
Weighted-average exercise price, Granted								1.40	5.04	8.43
Weighted-average exercise price, Vested								6.64	14.84	12.50
Weighted-average exercise price, Cancelled								5.86	12.74	18.55
Weighted-average exercise price, Ending balance			$ 5.93	$ 2.23				$ 2.23	$ 5.93	$ 13.57