Warrant Liabilities - Additional Information (Detail) - USD ($)				1 Months Ended	3 Months Ended	11 Months Ended	12 Months Ended
	Mar. 06, 2015	Mar. 05, 2015	Nov. 18, 2014	Jul. 31, 2015	Dec. 31, 2015	Feb. 12, 2016	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2015
Class of Warrant or Right [Line Items]
Liquidated damages amount percent of VWAP (percent)							1.00%
Change in fair value of warrants recorded as other (income) expense							$ 515,860	$ 3,941,335
Warrants cashless exercised							43,720
Issuance of shares upon cashless exercise warrants							13,407
Proceeds from issuance of common stock under tender offer							$ 1,434,194	0
Common Stock [Member]
Class of Warrant or Right [Line Items]
Issuance of shares upon cashless exercise warrants							5,879,560
Series A Warrants to Purchase Shares of Common Stock [Member] | IPO [Member]
Class of Warrant or Right [Line Items]
Number of common stock purchased upon issuance of warrants			2,449,605
Exercise price of warrants exercised			$ 6.50
Warrants term			5 years
Series A Warrant Liability [Member]
Class of Warrant or Right [Line Items]
Warrants exercised					24,000		24,000
Number of warrants					2,425,605		2,425,605
Fair value of warrants outstanding					$ 1,200,000		$ 1,200,000
Change in fair value of warrants recorded as other (income) expense							400,000
Proceeds from exercise of warrants	$ 200,000						$ 156,000	0
Series B Warrants to Purchase Shares of Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of common stock purchased upon issuance of warrants					2,449,605		2,449,605
Exercise price of warrants exercised					$ 6.50		$ 6.50
Warrants term							15 months
Series B Warrants to Purchase Shares of Common Stock [Member] | Scenario Forecast [Member]
Class of Warrant or Right [Line Items]
Decrease in common stock market price						$ 6.50
Series B Warrant Liability [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants exercised		$ 6.50
Warrants exercised		589,510
Number of warrants					116,580		116,580
Warrants cashless exercised							1,713,045
De-recognition of warrant liability		$ 6,700,000					$ 12,500,000
Proceeds from exercise of warrants		$ 3,800,000					3,720,713	$ 0
Series B Warrant Liability [Member] | Decrease in carrying value [Member]
Class of Warrant or Right [Line Items]
Change in fair value of warrants recorded as other (income) expense					$ 2,700,000		$ 16,600,000
Series C Warrant Liability [Member]
Class of Warrant or Right [Line Items]
Number of common stock purchased upon issuance of warrants					590,415		590,415
Exercise price of warrants exercised		$ 6.25							$ 6.25
Fair value of warrants outstanding					$ 500,000		$ 500,000
Change in fair value of warrants recorded as other (income) expense							$ 2,600,000
Warrants cashless exercised				905
Proceeds from issuance of common stock under tender offer				$ 5,882
Series C Warrant Liability [Member] | Common Stock [Member]
Class of Warrant or Right [Line Items]
Issuance of shares upon cashless exercise warrants				905