Warrants - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Aug. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Class of Warrant or Right [Line Items]
Warrants outstanding		2,350,085	612,112	2,350,085	612,112	4,658.000		616,770	477,613.000	208.614
Shares of common stock called by warrants							49,776
Issuances	2,345,427	2,345,427	134,499	2,395,203	403,498
Warrants right grant date fair value		$ 3,498,720		$ 3,498,720
Warrants right weighted average exercise price		$ 2.70		$ 2.70			$ 0.01
Merger Agreement [Member]
Class of Warrant or Right [Line Items]
Number of warrants exercised				660,715
Maximum [Member]
Class of Warrant or Right [Line Items]
Shares of common stock called by warrants							49,776