Comprehensive (Loss) Income - Components of Accumulated Other Comprehensive (Loss) Income (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Apr. 30, 2018
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Foreign currency translation adjustments	$ (46,961)	$ (32,399)
Deferred compensation and pension plan adjustments, net of tax	(11,196)	(9,073)
Interest rate swap unrealized gain, net of taxes	1,669	1,337
Accumulated other comprehensive loss, net	$ (56,488)	$ (40,135)

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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