QUARTERLY UNAUDITED INFORMATION (Details) - Schedule of Quarterly Financial Information - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended																12 Months Ended
	Jan. 31, 2021		Oct. 31, 2020		Jul. 31, 2020		Apr. 30, 2020		Jan. 31, 2020		Oct. 31, 2019		Jul. 31, 2019		Apr. 30, 2019		Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Schedule of Quarterly Financial Information [Abstract]
Net sales and revenue	$ 126,018		$ 124,251		$ 39,327		$ 83,250		$ 120,920		$ 86,671		$ 105,868		$ 104,575		$ 372,846	$ 418,034	$ 486,671
Gross (loss) profit	6,843		17,679		(1,331)		(9,330)		6,593		(1,758)		4,004		3,646		13,861	12,485	30,215
Net (loss) income	5,022		11,059		(2,033)		(8,430)		6,249		(1,673)		3,353		3,715		5,618	11,644	37,510
Net (loss) income attributable to REX common shareholders	$ 3,543		$ 8,841		$ (1,748)		$ (7,635)		$ 4,402		$ (2,052)		$ 2,256		$ 2,821		$ 3,001	$ 7,427	$ 31,645
Basic and diluted net (loss) income per share attributable to REX common shareholders ( (in Dollars per share)	$ 0.59	[1]	$ 1.44	[1]	$ (0.28)	[1]	$ (1.21)	[1]	$ 0.70	[1]	$ (0.32)	[1]	$ 0.36	[1]	$ 0.45	[1]	$ 0.49	$ 1.18	$ 4.91

[1] The total of the quarterly net income per share amounts do not equal the annual net income per share amounts due to the impact of varying amounts of shares outstanding during the year.