Stock Option Plans - Summary of Company's Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Number of Shares (in thousands)
Outstanding, beginning (in shares)	2,172,000
Granted (in shares)	441,000		0
Exercised (in shares)	0	0	0
Forfeited (in shares)	(15,000)
Expired (in shares)	(435,000)
Outstanding, ending (in shares)	2,163,000	2,172,000
Exercisable (in shares)	1,371,000
Vested and expected to vest (in shares)	2,145,000
Weighted Average Exercise Price
Outstanding beginning (in usd per share)	$ 7.75
Granted (in usd per share)	3.69
Exercised (in usd per share)	0.00
Forfeited (in usd per share)	19.06
Expired (in usd per share)	15.74
Outstanding ending (in usd per share)	5.24	$ 7.75
Exercisable (in usd per share)	6.12
Vested and expected to vest (in usd per share)	$ 5.40
Weighted Average Remaining Contractual Term, outstanding	6 years 6 months 15 days	6 years 1 month 28 days
Weighted Average Remaining Contractual Term, exercisable	5 years 2 months 9 days
Weighted Average Remaining Contractual Term, Vested and expected to vest	6 years 5 months 27 days
Aggregate Intrinsic Value, Outstanding	$ 526	$ 320
Aggregate Intrinsic Value, Exercisable	399
Aggregate Intrinsic Value, Vested and expected to vest	$ 516

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.