Fair Value Measurements (Details 1) - Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance, beginning of period		$ 6,300	$ 2,000
Transfer into Level 3 from adoption of change in accounting for equity investments	2,793
Total gains included in "Other income (expense), net"	826
Total gains included in other comprehensive income			2,100
Purchases			2,200
Rafael Spin-Off		(6,300)
Balance, end of period	3,619		6,300
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the period	$ 826