STOCK-BASED COMPENSATION - Summary of Change in Number of Non-Vested Options to Purchase Shares of Common Stock (Details) - $ / shares shares in Thousands	9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019
STOCK-BASED COMPENSATION
Shares, Non-vested, Beginning balance	448	375
Shares, Granted	172	168
Shares, Vested	(112)	(57)
Shares, Forfeitures	(9)	(28)
Shares, Non-vested, Ending balance	499	458
Weighted Average Fair Value, Non-vested, Beginning balance	$ 9.74	$ 10.05
Weighted Average Fair Value, Granted	5.68	10.32
Weighted Average Fair Value, Vested	9.81	9.28
Weighted Average Fair Value, Forfeitures	8.08	10.47
Weighted Average Fair Value, Non-vested, Ending balance	$ 8.35	$ 10.22