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Equity and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Quarterly dividends declared (in usd per share)	$ 0.5625
Average option price (in dollars per share)	$ 3.72
Compensation expense related to stock-based awards granted	$ 270	$ 207	$ 611	$ 575
Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	80,000		80,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	5,500		5,500
Grant price (in dollars per share)	$ 3.95