CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]
Balance (in shares) at Jan. 31, 2019		31,788,162
Balance at Jan. 31, 2019	$ 619,975	$ 318	$ 111,185	$ 508,472
Exercise of options and vesting of restricted stock, net of tax (in shares)		136,206
Exercise of options and vesting of restricted stock, net of withholding tax	(1,240)	$ 1	(1,241)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		12,158
Issuance of common stock under Employee Stock Purchase Plan	198		198
Stock-based compensation	3,217		3,217
Net income (loss)	19,509			19,509
Balance (in shares) at Apr. 30, 2019		31,936,526
Balance at Apr. 30, 2019	647,819	$ 319	113,359	534,141
Balance (in shares) at Jan. 31, 2020		32,125,055			(3,485,441)
Balance at Jan. 31, 2020	627,180	$ 321	122,513	570,636	$ (66,290)
Exercise of options and vesting of restricted stock, net of tax (in shares)		321,468
Exercise of options and vesting of restricted stock, net of withholding tax	(1,285)	$ 3	(1,288)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		47,450
Issuance of common stock under Employee Stock Purchase Plan	177	$ 1	176
Stock-based compensation	2,430		2,430
Net income (loss)	(56,202)			(56,202)
Balance (in shares) at Apr. 30, 2020		32,493,973			(3,485,441)
Balance at Apr. 30, 2020	$ 495,809	$ 325	$ 123,831	$ 437,943	$ (66,290)