Stock Option Plans - Additional Information (Detail)	12 Months Ended
	Jan. 31, 2018 USD ($) $ / shares shares	Jan. 31, 2017 USD ($) shares	Jan. 31, 2016 USD ($) $ / shares shares
Stock Based Compensation [Line Items]
Compensation expense related to stock-based awards granted	$ 903,000	$ 737,000	$ 1,300,000
Number of options granted | shares	549,000	0
Weighted average grant-date fair value of options granted | $ / shares	$ 2.02		$ 1.64
Excess tax benefit from share-based compensation	$ 0	$ 0	$ (416,000)
Number of plans with share-based awards outstanding	5
Number of options exercised | shares	0	0	0
Fair value of options vested	$ 500,000	$ 1,000,000	$ 1,500,000
Options vested | shares	245,000
Total unrecognized compensation expense related to unvested stock options	$ 578,000
Expense expected to be recognized over weighted average period	10 months 10 days
Restricted Stock
Stock Based Compensation [Line Items]
Expense expected to be recognized over weighted average period	7 months 6 days
Total unrecognized compensation expense related to unvested restricted stock awards	$ 2,000
2006 Plan
Stock Based Compensation [Line Items]
Vesting period of stock options granted and outstanding	3 years
Contractual term of stock options granted and outstanding	10 years
Shares available for grant | shares	218,000
1994 Plan
Stock Based Compensation [Line Items]
Vesting period of stock options granted and outstanding	3 years
Contractual term of stock options granted and outstanding	10 years
1998 Plan
Stock Based Compensation [Line Items]
Vesting period of stock options granted and outstanding	3 years
Contractual term of stock options granted and outstanding	10 years
2000 Plan
Stock Based Compensation [Line Items]
Vesting period of stock options granted and outstanding	3 years
Contractual term of stock options granted and outstanding	10 years
Director Plan
Stock Based Compensation [Line Items]
Vesting period of stock options granted and outstanding	1 year
Contractual term of stock options granted and outstanding	10 years