Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Increase (Decrease) in Stockholders' Equity
Beginning Balance	$ 661,537	$ 608,867	$ 523,932
Total other comprehensive loss:	(5,402)	(10,741)	(1,556)
Ending Balance	729,599	661,537	608,867
Interest expense, next twelve months	(5,484)
Interest rate swap \| Interest expense
Increase (Decrease) in Stockholders' Equity
Current year interest expense	1,562
Total
Increase (Decrease) in Stockholders' Equity
Beginning Balance	(22,197)	(11,456)	(9,900)
Total other comprehensive loss:	(5,402)	(10,741)	(1,556)
Ending Balance	(27,599)	(22,197)	(11,456)
Foreign Currency Translation Adjustments
Increase (Decrease) in Stockholders' Equity
Beginning Balance	(24,743)	(11,456)	(9,900)
Other comprehensive income (loss), before tax	11,951	(13,287)	(1,556)
Ending Balance	(12,792)	(24,743)	(11,456)
Changes in Fair Value of Interest Rate Swaps(1)
Increase (Decrease) in Stockholders' Equity
Beginning Balance	3,312	0	0
Other comprehensive income (loss), before tax	(22,905)	3,312	0
Ending Balance	(19,593)	3,312	0
Tax effects
Increase (Decrease) in Stockholders' Equity
Beginning Balance	(766)	0	0
Other comprehensive income (loss), tax	5,552	(766)	0
Ending Balance	$ 4,786	$ (766)	$ 0

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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