Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Data (Unaudited) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net revenues:	$ 12,328	$ 14,651	$ 8,350	$ 7,613	$ 10,363	$ 8,644	$ 10,836	$ 18,433	$ 42,942	$ 48,276	$ 40,999
Gross profit (loss):	3,411	5,224	1,860	1,245	1,371	901	618	3,194	11,740	6,084	(7,414)
Loss before income taxes:	(4,176)	(5,440)	(4,504)	(5,468)	(8,021)	(4,695)	(5,007)	(2,436)	(19,588)	(20,159)	(31,339)
Incomes taxes (benefit):	(21)	(249)	85	437	(262)	586	357	229	252	910	1,814
Net loss:	$ (4,155)	$ (5,191)	$ (4,589)	$ (5,905)	$ (7,759)	$ (5,281)	$ (5,364)	$ (2,665)	$ (19,840)	$ (21,069)	$ (33,153)
Loss per common share – basic (in usd per share)	$ (0.38)	$ (0.47)	$ (0.41)	$ (0.52)	$ (0.66)	$ (0.46)	$ (0.46)	$ (0.24)	$ (1.78)	$ (1.82)	$ (2.79)
Income per common share – diluted (in usd per share)	$ (0.38)	$ (0.47)	$ (0.41)	$ (0.52)	$ (0.66)	$ (0.46)	$ (0.46)	$ (0.24)	$ (1.78)	$ (1.82)	$ (2.79)