PENSION AND OTHER POSTRETIREMENT BENEFITS Components of net periodic benefit cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017
Pension Benefits
Defined Benefit Plans and Postretirement Health Benefits
Service cost	$ 1,723	$ 1,826
Interest cost	2,022	1,861
Expected return on plan assets	(2,168)	(1,774)
Amortization of: Prior service costs (income)	2	2
Amortization of: Other actuarial loss	1,274	1,828
Net periodic benefit cost	2,853	3,743
Postretirement Health Benefits
Defined Benefit Plans and Postretirement Health Benefits
Service cost	106	125
Interest cost	84	78
Expected return on plan assets	0	0
Amortization of: Prior service costs (income)	(6)	(6)
Amortization of: Other actuarial loss	0	41
Net periodic benefit cost	$ 184	$ 238