Derivative Instruments (Details 1) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Apr. 30, 2019	Jul. 31, 2018
Derivatives not designated or not qualifying as hedging instruments:
Foreign exchange forward contracts	$ 96	$ 41
Balance Sheet Location	Accrued expenses	Accrued expenses

Description of where the foreign currency derivatives are reported in the balance sheet.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n)(7))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c),(d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration