Stockholders' Equity - Accumulated Other Comprehensive Loss (Details) $ in Thousands	3 Months Ended
Jul. 31, 2020 USD ($)
Accumulated other comprehensive (loss) income
Balance	$ 633,981
Balance	681,871
Other comprehensive loss on derivative instruments before reclassification, tax	300
Accumulated Other Comprehensive Loss
Accumulated other comprehensive (loss) income
Balance	(65,082)
Other comprehensive income before reclassification	17,240
Balance	(47,842)
Foreign Currency Translation
Accumulated other comprehensive (loss) income
Balance	(40,577)
Other comprehensive income before reclassification	16,281
Balance	(24,296)
Derivative Financial Instruments
Accumulated other comprehensive (loss) income
Balance	(24,505)
Other comprehensive income before reclassification	959
Balance	$ (23,546)

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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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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