Fair Value Measurements (Details 1) - Level 3 [Member] - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2018	Oct. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance, beginning of period		$ 6,300
Transfer into Level 3 from adoption of change in accounting for equity investments	2,794
Total gains recognized in "Other expense, net"	22
Balance, end of period	2,816	6,300
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the period	$ 22