Stock Option Plans - Summary of Company's Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Number of Shares (in thousands)
Outstanding, beginning (in shares)	2,163,000
Granted (in shares)	640,000
Exercised (in shares)	(9,000)	0	0
Forfeited (in shares)	(88,000)
Expired (in shares)	(266,000)
Outstanding, ending (in shares)	2,440,000	2,163,000
Exercisable (in shares)	1,461,000
Vested and expected to vest (in shares)	2,400,000
Weighted Average Exercise Price
Outstanding beginning (in usd per share)	$ 7.75
Granted (in usd per share)	3.96
Exercised (in usd per share)	2.80
Forfeited (in usd per share)	3.73
Expired (in usd per share)	29.86
Outstanding ending (in usd per share)	4.51	$ 7.75
Exercisable (in usd per share)	4.87
Vested and expected to vest (in usd per share)	$ 4.50
Weighted Average Remaining Contractual Term, outstanding (in years)	7 years 29 days	6 years 6 months 15 days
Weighted Average Remaining Contractual Term, exercisable (in years)	5 years 11 months 9 days
Weighted Average Remaining Contractual Term, Vested and expected to vest (in years)	7 years 7 days
Aggregate Intrinsic Value, Outstanding	$ 20	$ 526
Aggregate Intrinsic Value, Exercisable	15
Aggregate Intrinsic Value, Vested and expected to vest	$ 20