Consolidated Statements of Comprehensive Income Statement - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ (19,665)	$ 21,224	$ 14,976
Other comprehensive income (loss):
Foreign currency translation adjustments	(1,567)	1,179	(562)
Unrealized (loss) gain on available-for-sale securities, net of tax benefit (expense) of $233, $234, and $(187), respectively	(363)	(231)	288
Reclassification adjustment for realized (gain) loss on available-for-sale securities, included in net income	(22)	(151)	24
Other comprehensive income (loss)	(1,952)	797	(250)
Comprehensive income (loss)	$ (21,617)	$ 22,021	$ 14,726