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Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position - USD ($) $ in Thousands | Jan. 31, 2021 | Jul. 31, 2020
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Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position [Line Items] |  |
Unrealized Losses | $ 26 |
Fair Value | 3,357 |
U.S. Treasury bills and notes [Member] |  |
Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position [Line Items] |  |
Unrealized Losses | 9 |
Fair Value | 1,667 |
Corporate bonds [Member] |  |
Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position [Line Items] |  |
Unrealized Losses | 17 |
Fair Value | $ 1,690 |
Municipal Bonds [Member] |  |
Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position [Line Items] |  |
Unrealized Losses |  | $ 16
Fair Value |  | $ 1,963

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- References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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