Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended	9 Months Ended
	Jan. 06, 2017	Apr. 15, 2015 $ / shares	Oct. 31, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares	Sep. 30, 2015 USD ($)	Dec. 31, 2015 $ / shares
Subsequent Event [Line Items]
Common stock, par value | $ / shares		$ 0.01		$ 0.01		$ 0.01
Reverse split of common stock				one-for-fifteen
Reverse stock split ratio		0.067
Proceeds from the exercise of warrants | $				$ 10,895	$ 10,151
Minimum | Scenario, Forecast
Subsequent Event [Line Items]
Reverse split of common stock	one-for-two
Reverse stock split ratio	0.5
Maximum | Scenario, Forecast
Subsequent Event [Line Items]
Reverse split of common stock	one-for-twenty
Reverse stock split ratio	0.05
Subsequent Event
Subsequent Event [Line Items]
Common stock, par value | $ / shares			$ 0.01
Subsequent Event | Series F Warrant
Subsequent Event [Line Items]
Common stock, issued | shares			4,677,143
Proceeds from the exercise of warrants | $			$ 1,400