Investments (Details) - USD ($) |
3 Months Ended | ||
|---|---|---|---|
Apr. 30, 2026 |
Apr. 30, 2025 |
Jan. 31, 2026 |
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| Investments [Abstract] | |||
| Debt securities, held-to-maturity, amortized cost, before allowance for credit loss | $ 246,600,000 | $ 187,000,000 | |
| Debt securities, held-to-maturity, weighted average yield, maturity, year one | 3.70% | 3.80% | |
| Debt securities, held-to-maturity, accumulated unrecognized loss | $ 107,000 | $ 52,000 | |
| Big River [Member] | |||
| Investments [Abstract] | |||
| Retained earnings, undistributed earnings from equity method investees | 21,300,000 | $ 17,700,000 | |
| Proceeds from equity method investments, dividend distribution | $ 0 | $ 0 | |
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- Definition Weighted average yield of investment in debt security measured at amortized cost (held-to-maturity) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Dividends received on equity and other investments during the current period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50 percent or less owned persons accounted for by the equity method (equity method investees). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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