CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (6,159)	$ (9,627)	$ (4,924)	$ (28,745)
Other comprehensive loss:
Foreign currency translation adjustment	(3,064)	(608)	(2,387)	(276)
Net unrealized holding gain (loss) on securities, net of tax	0	3	(96)	(86)
Pension liability adjustments, net of tax	(129)	0	(131)	(64)
Other comprehensive loss	(3,193)	(605)	(2,614)	(426)
Comprehensive loss	$ (9,352)	$ (10,232)	$ (7,538)	$ (29,171)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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