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Accounting Policies (Details) - USD ($)	6 Months Ended		12 Months Ended
Accounting Policies (Details) - USD ($)	Jul. 31, 2026	Jul. 31, 2025	Jan. 31, 2026	Jan. 31, 2025
Accounting Policies [Abstract]
Accounts receivables	$ 23,479,000		$ 14,682,000	$ 21,500,000
Income taxes paid	800,000	$ 3,100,000
Proceeds from income tax refunds	0	0
Unrecognized tax benefits	396,000	$ 18,991,000	383,000	$ 18,978,000
Accrued penalties and interest	137,000		124,000
Decrease in provision for income taxes	175,000
Inventory write-down	0		66,000
Approximation [Member]
Accounting Policies [Abstract]
Unrecognized tax benefits	$ 259,000		$ 259,000
Minimum [Member] \| Buildings and Improvements [Member]
Accounting Policies [Abstract]
Property, plant and equipment, useful life	15 years
Minimum [Member] \| Fixtures and Equipment [Member]
Accounting Policies [Abstract]
Property, plant and equipment, useful life	3 years
Maximum [Member] \| Buildings and Improvements [Member]
Accounting Policies [Abstract]
Property, plant and equipment, useful life	40 years
Maximum [Member] \| Fixtures and Equipment [Member]
Accounting Policies [Abstract]
Property, plant and equipment, useful life	40 years
Maximum [Member] \| Rex American Resources [Member]
Accounting Policies [Abstract]
Ownership percentage	20.00%