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Debt Securities (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jan. 31, 2020 | Jan. 31, 2019 | Jan. 31, 2020 | Jan. 31, 2019
Debt Securities (Textual) |  |  |  |
Proceeds from maturities and sales of available-for-sale securities | $ 1,900 | $ 2,200 | $ 2,700 | $ 5,600
Realized losses from sales of available-for-sale debt securities |  |  |  |
Realized gains from sales of available-for-sale debt securities |  |  |  |

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- Definition Marketable Securities Textual. + References No definition available. + Details
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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- Definition Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3151-108585 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562 + Details
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