Comprehensive Income - Changes in Each Component of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 31, 2023	Jan. 31, 2022	Jan. 31, 2023	Jan. 31, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 1,544,346
Unrealized (losses) gains arising during the period	$ 39,803	$ (14,523)	(4,782)	$ (29,911)
Reclassification of realized net losses to net income	60	335	165	1,013
Ending balance	1,608,979		1,608,979
Tax effect on unrealized gains, securities	100
Tax effect on unrealized gains (losses), pensions		300		300
Tax effect on reclassification of realized (gains) losses		100	100	300
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(136,665)	(66,530)	(92,185)	(51,820)
Ending balance	(96,802)	(80,718)	(96,802)	(80,718)
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(136,991)	(49,051)	(92,717)	(33,666)
Unrealized (losses) gains arising during the period	39,482	(15,232)	(4,792)	(30,617)
Reclassification of realized net losses to net income	0	0	0	0
Ending balance	(97,509)	(64,283)	(97,509)	(64,283)
Deferred Compensation and Pension Plan
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	1,066	(17,443)	961	(18,135)
Unrealized (losses) gains arising during the period	0	824	0	839
Reclassification of realized net losses to net income	60	335	165	1,012
Ending balance	1,126	(16,284)	1,126	(16,284)
Unrealized Losses on Marketable Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(740)	(36)	(429)	(19)
Unrealized (losses) gains arising during the period	321	(115)	10	(133)
Reclassification of realized net losses to net income	0	0	0	1
Ending balance	$ (419)	$ (151)	$ (419)	$ (151)

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

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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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