Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Apr. 30, 2020	Apr. 30, 2019
Components and changes in accumulated other comprehensive (loss) income
Beginning Balance	$ 723,281	$ 732,191	$ 661,537	$ 641,603	$ 622,360	$ 608,867	$ 661,537	$ 608,867
Other comprehensive income (loss)	(25,178)	106	5,177	(2,559)	(417)	(5,223)	(19,895)	(8,199)
Ending Balance	688,469	723,281	732,191	655,865	641,603	622,360	688,469	655,865
Tax effect on interest rate swap	6,098			6,098			5,576	5,576
Accumulated Other Comprehensive Loss
Components and changes in accumulated other comprehensive (loss) income
Beginning Balance	(16,914)	(17,020)	(22,197)	(17,096)	(16,679)	(11,456)	(22,197)	(11,456)
Other comprehensive income (loss)	(25,178)	106	5,177	(2,559)	(417)	(5,223)
Ending Balance	(42,092)	$ (16,914)	$ (17,020)	(19,655)	$ (17,096)	$ (16,679)	(42,092)	(19,655)
Foreign Currency Translation
Components and changes in accumulated other comprehensive (loss) income
Other comprehensive income (loss)	(6,053)			(3,168)			(2,261)	(8,808)
Interest Rate Swap, net of taxes
Components and changes in accumulated other comprehensive (loss) income
Other comprehensive income (loss)	$ (19,125)			$ 609			$ (17,634)	$ 609

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, after adjustments, of tax expense (benefit) for gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge, attributable to attributable to parent. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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