Employee Benefit Plans - Schedule of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Net periodic postretirement benefit cost included the following components:
Service cost	$ 210	$ 674	$ 770
Interest cost	222	534	476
Amortization of prior service credit	(1,169)	(203)	(203)
Amortization of net actuarial gain	(804)	(265)	(47)
Curtailment gain	(4,296)	0	0
Periodic postretirement benefit cost	$ (5,837)	$ 740	$ 996