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
	Apr. 30, 2023	Apr. 30, 2022
Net Income per Common Share
Net income (loss) attributable to G-III Apparel Group, Ltd.	$ 3,236	$ 30,634
Basic net income (loss) per share:
Basic common shares	46,286	48,016
Basic net income (loss) per share (in dollars per share)	$ 0.07	$ 0.64
Diluted net income (loss) per share:
Basic common shares	46,286	48,016
Diluted restricted stock awards and stock options	1,156	1,092
Diluted common shares	47,442	49,108
Diluted net income (loss) per share (in dollars per share)	$ 0.07	$ 0.62