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Equity Investments (Details) - Equity investments [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Apr. 30, 2019	Apr. 30, 2019
Equity Securities without Readily Determinable Fair Value [Line Items]
Balance, beginning of period	$ 3,045	$ 1,883
Adoption of change in accounting for equity investments		1,213
Adjusted balance, beginning of period	3,045	3,096
Adjustment for observable transactions involving a similar investment from the same issuer	599	550
Redemptions		(2)
Impairments
Balance, end of period	$ 3,644	$ 3,644

X

- Definition

Amount of equity investments adjustment.

+ References

No definition available.

+ Details

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- Definition

Equity securities without readily determinable fair value, redemptions, annual amount.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

Amount of impairment loss on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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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.

+ References

No definition available.

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- Definition

Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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