Comprehensive Income - Changes in Each Component of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2024	Jul. 31, 2023
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 1,737,325	$ 1,653,005
Ending balance	1,759,242	1,692,530
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(107,671)	(92,764)
Unrealized gains arising during the period	2,861	2,266
Reclassification of realized net gains to net income	(50)	27
Ending balance	(104,860)	(90,471)
Foreign Currency Translation
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(116,004)	(96,860)
Unrealized gains arising during the period	2,797	2,131
Reclassification of realized net gains to net income	0	0
Ending balance	(113,207)	(94,729)
Deferred Compensation and Pension Plan
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	8,370	4,381
Unrealized gains arising during the period	0	0
Reclassification of realized net gains to net income	(50)	27
Ending balance	8,320	4,408
Unrealized Losses on Marketable Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(37)	(285)
Unrealized gains arising during the period	64	135
Reclassification of realized net gains to net income	0	0
Ending balance	$ 27	$ (150)