Net Loss per Share - Computation of Denominators Used in Net Loss per Share Available to Common Stockholders (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Basic:
Weighted average shares outstanding	24,620,372	20,965,935	4,133,138
Diluted:
Weighted average shares outstanding - Basic	24,620,372	20,965,935	4,133,138
Convertible preferred stock	0	0	0
Common stock options	0	0	0
Common stock warrants	0	0	0
Convertible promissory notes (as converted)	0	0	0
Denominator for diluted net loss per share available to common stockholders	24,620,372	20,965,935	4,133,138