Net Income per Common Share - Reconciliation between basic and diluted net income per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2023	Jul. 31, 2022
Net Income per Common Share
Net Income (Loss)	$ 16,438	$ 36,319	$ 19,674	$ 66,953
Basic net income (loss) per share:
Basic common shares	45,714	47,999	45,996	48,007
Basic net income (loss) per share (in dollars per share)	$ 0.36	$ 0.76	$ 0.43	$ 1.39
Diluted net income (loss) per share:
Basic common shares	45,714	47,999	45,996	48,007
Diluted restricted stock awards and stock options	856	1,020	996	1,054
Diluted common shares	46,570	49,019	46,992	49,061
Diluted net income (loss) per share (in dollars per share)	$ 0.35	$ 0.74	$ 0.42	$ 1.36