Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	May. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum amount of common stock authorized to offer	$ 50,000		$ 36,600
Commission on aggregate gross proceeds from sale of common stock	2.00%
Proceeds from issuance of common stock	$ 3,486	$ 0
Weighted average life [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average price of shares sold	$ 6.37