Employee Savings Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Employee Savings Plan
Amount of expense in contribution to the plan	$ 6,842	$ 5,764	$ 4,744

Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

Name:	us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration