Short-term investments Short-Term Investments Total current assets Operating lease right-of-use assets Total assets Current operating lease liabilities Total current liabilities Long-term operating lease liabilities Total long-term liabilities Total REX shareholders’ equity Total equity Balance Balance Total liabilities and equity Gross profit Gross profit Income before income taxes Net income Income from continuing operations Net income attributable to REX common shareholders Balance (in Shares) Balance (in Shares) Equity Components [Axis] Net cash provided by operating activities Net cash used in investing activities Net cash used in financing activities Net increase (decrease) in cash, cash equivalents and restricted cash Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Total cash, cash equivalents and restricted cash Table Period [Axis] Revision of Prior Period [Axis] Total Inventory Segments [Axis] Total lease expense Total Operating lease liabilities Total liabilities Total assets Fair Value Hierarchy and NAV [Axis] Total Property and equipment, net Total Accrued transportation related items Total Accrued expenses and other current liabilities Derivative Instrument [Axis] Investment, Name [Axis] Non-Vested Shares, Beginning of Period Non-Vested Shares, End of Period Weighted Average Grant Date Fair Value, Beginning of Period (in Dollars) Weighted Average Grant Date Fair Value, End of Period (in Dollars) Unrecognized tax benefits, beginning of period Unrecognized tax benefits, end of period Document Type Document Quarterly Report Document Period End Date Document Transition Report Entity File Number Entity Registrant Name Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Address, Address Line One Entity Address, City or Town Entity Address, State or Province Entity Address, Postal Zip Code City Area Code Local Phone Number Title of 12(b) Security Trading Symbol Security Exchange Name Entity Current Reporting Status Entity Interactive Data Current Entity Filer Category Entity Small Business Entity Emerging Growth Company Entity Shell Company Entity Common Stock, Shares Outstanding Amendment Flag Current Fiscal Year End Date Document Fiscal Period Focus Document Fiscal Year Focus Entity Central Index Key Assets: Current assets: Cash and cash equivalents Restricted cash Accounts receivable Refundable income taxes Prepaid expenses and other Other assets Equity method investment Big River Liabilities and equity: Current liabilities: Accounts payable – trade (includes $1.9 million and $1.5 million with related parties at October 31, 2023 and January 31, 2023, respectively) Accounts payable, related parties Accounts Payable Related Parties Long-term liabilities: Deferred taxes Other long-term liabilities Equity: REX shareholders’ equity: Common stock Paid-in capital Retained earnings Noncontrolling interests Net sales and revenue Sales of products, continuing operations Cost of sales (includes $32,723 and $35,155 with related parties for the quarters ended October 31, 2023 and 2022, respectively, and $92,610 and $101,240 with related parties for the nine months ended October 31, 2023 and 2022, respectively) Cost of sales Cost of sales, related parties Equity in income of unconsolidated affiliates Income from equity method investments Interest and other income, net Weighted average shares outstanding – basic and diluted (in Shares) Basic and diluted net income per share attributable to REX common shareholders (in Dollars per share) Net income Issuance of equity awards and stock based compensation expense Issuance of equity awards and stock based compensation expense (in Shares) Treasury stock acquired (in Shares) Cash flows from operating activities: Net income including noncontrolling interests Adjustments to reconcile net income to net cash provided by operating activities: Depreciation Amortization of operating lease right-of-use assets Deferred income tax Stock based compensation expense Changes in assets and liabilities: Accounts payable, trade Other liabilities Cash flows from investing activities: Maturity of short-term investments Proceeds from sale of real estate and property and equipment Cash flows from financing activities: Payments to noncontrolling interests holders Non cash investing activities – Accrued capital expenditures Non cash financing activities – Stock awards accrued Non cash financing activities – Stock awards issued Right-of-use assets acquired and liabilities incurred upon lease execution Reconciliation of total cash, cash equivalents and restricted cash: Treasury stock Selling, general and administrative expenses Selling, general and administrative Provision for income taxes Income Tax Expense (Benefit) Net income attributable to noncontrolling interests Noncontrolling interests distribution and other Treasury stock acquired Dividends received from equity method investments Interest income from investments Loss (gain) on sale of property and equipment – net Accounts receivable Inventories Refundable income taxes Other assets Capital expenditures Purchase of short-term investments Deposits Treasury stock acquired Common Stock [Member] Treasury Stock, Common [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Noncontrolling Interest [Member] Condensed Financial Information of Parent Company Only Disclosure [Text Block] Significant Accounting Policies [Text Block] Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] Schedule of Inventory, Current [Table Text Block] Ethanol and other finished goods Work in process Corn and other raw materials Revenue from Contract with Customer [Text Block]