Stockholders' Equity - Summary of Outstanding Warrants (Detail) - Warrants [Member] - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Class Of Warrant Or Right [Line Items]
Balance outstanding, Beginning, Number of Warrants	716,748
Warrants expired, Number of Warrants	(716,748)
Balance outstanding, Ending, Number of Warrants	0	716,748
Balance outstanding, Beginning, Weighted Average Exercise Price	$ 15.98
Warrants expired, Weighted Average Exercise Price	$ 15.98
Balance outstanding, Ending, Weighted Average Exercise Price		$ 15.98
Balance outstanding, Weighted Average Remaining Contractual Life (in years)		2 months 12 days