CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)		12 Months Ended
		Jan. 31, 2023	Jan. 31, 2022	Jan. 31, 2021
Income Statement [Abstract]
Net sales and revenue		$ 855,000,000	$ 774,802,000	$ 372,664,000
Cost of sales (includes $135.4 million, $90.2 million and $54.8 million with related parties for the years ended January 31, 2023, 2022 and 2021, respectively)		800,269,000	677,242,000	353,131,000
Gross profit		54,731,000	97,560,000	19,533,000
Selling, general and administrative expenses		(28,956,000)	(28,476,000)	(17,639,000)
Equity in income of unconsolidated affiliates		8,745,000	6,624,000	500,000
Interest and other income, net		12,959,000	130,000	1,818,000
Income before income taxes		47,479,000	75,838,000	4,212,000
(Provision) benefit for income taxes		(9,542,000)	(19,031,000)	546,000
Net income from continuing operations		37,937,000	56,807,000	4,758,000
Net income attributable to noncontrolling interests (continuing operations)		(10,240,000)	(9,235,000)	(2,878,000)
Net income attributable to REX common shareholders (continuing operations)		27,697,000	47,572,000	1,880,000
Net income from discontinued operations, net of tax (includes expense of $0.3 million and $(0.2) million with related parties for the years ended January 31, 2022 and 2021, respectively.			4,395,000	860,000
Net loss attributable to noncontrolling interests (discontinued operations)	[1]		397,000	261,000
Net income attributable to REX common shareholders (discontinued operations)			4,792,000	1,121,000
Net income attributable to REX common shareholders		27,697,000	52,364,000	3,001,000
Weighted average shares outstanding – basic and diluted		17,638,000	17,946,000	18,502,000
Basic and diluted net income per share from continuing operations attributable to REX common shareholders		1.57	2.65	0.1
Basic and diluted net income per share from discontinued operations attributable to REX common shareholders			0.27	0.06
Basic and diluted net income per share attributable to REX common shareholders		$ 1.57	$ 2.92	$ 0.16

[1] Net loss attributable to noncontrolling interest represents the minority investor’s share of the loss before income taxes as noncontrolling interests does not include any gain from the refined coal tax credits.