Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2021	Jul. 31, 2020
Change In Pension Benefits And Derivative Hedging Activities [Line Items]
Other comprehensive income, deferred tax	$ 126	$ 113

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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+ Details