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Fair Value Measurements (Details 1) - Level 3 [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jan. 31, 2020 | Jan. 31, 2019 | Jan. 31, 2020 | Jan. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Balance, beginning of period | $ 3,637 | $ 2,816 | $ 3,619 |
Transfer into Level 3 from adoption of change in accounting for equity investments |  |  |  | 2,794
Total gain (losses) recognized in "Other income (expense), net" | 408 | (71) | 426 | (49)
Balance, end of period | 4,045 | 2,745 | 4,045 | 2,745
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the period | $ 408 | $ (71) | $ 426 | $ (49)

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- Definition Amount of fair value measurement with unobservable inputs reconciliation recurring basis asset transfers into level three from adoption of accounting change. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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