Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Apr. 30, 2020		42,554
Beginning balance at Apr. 30, 2020	$ 633,981	$ 426	$ 529,662	$ 168,975	$ (65,082)
Increase (Decrease) in Stockholders' Equity
Net income	27,219			27,219
Foreign currency translation adjustments	16,281				16,281
Other comprehensive income, net of tax	959				959
Equity-based compensation	1,575		1,575
Exercise of stock options (in shares)		54
Exercise of stock options	691		691
Vesting of restricted stock units (in shares)		7
Tax withholding related to net share settlements of equity awards	(105)		(105)
Issuance of common stock pursuant to employee stock purchase plan (in shares)		58
Issuance of common stock pursuant to employee stock purchase plan	1,270	$ 1	1,269
Ending balance (in shares) at Jul. 31, 2020		42,673
Ending balance at Jul. 31, 2020	681,871	$ 427	533,092	196,194	(47,842)
Beginning balance (in shares) at Apr. 30, 2020		42,554
Beginning balance at Apr. 30, 2020	633,981	$ 426	529,662	168,975	(65,082)
Increase (Decrease) in Stockholders' Equity
Net income	71,814
Foreign currency translation adjustments	39,813
Other comprehensive income, net of tax	5,777
Ending balance (in shares) at Jan. 31, 2021		42,854
Ending balance at Jan. 31, 2021	761,014	$ 428	539,289	240,789	(19,492)
Beginning balance (in shares) at Jul. 31, 2020		42,673
Beginning balance at Jul. 31, 2020	681,871	$ 427	533,092	196,194	(47,842)
Increase (Decrease) in Stockholders' Equity
Net income	28,469			28,469
Foreign currency translation adjustments	3,159				3,159
Other comprehensive income, net of tax	2,844				2,844
Repurchase and retirement of common stock (in shares)		(50)
Repurchase and retirement of common stock	(1,222)	$ (1)	(1,221)
Equity-based compensation	3,253		3,253
Exercise of stock options (in shares)		5
Exercise of stock options	172		172
Vesting of restricted stock units (in shares)		62
Vesting of restricted stock units	0	$ 1	(1)
Tax withholding related to net share settlements of equity awards	(649)		(649)
Ending balance (in shares) at Oct. 31, 2020		42,690
Ending balance at Oct. 31, 2020	717,897	$ 427	534,646	224,663	(41,839)
Increase (Decrease) in Stockholders' Equity
Net income	16,126			16,126
Foreign currency translation adjustments	20,373				20,373
Other comprehensive income, net of tax	1,974				1,974
Repurchase and retirement of common stock (in shares)		(30)
Repurchase and retirement of common stock	(778)		(778)
Equity-based compensation	1,876		1,876
Exercise of stock options (in shares)		152
Exercise of stock options	2,793	$ 1	2,792
Vesting of restricted stock units (in shares)		4
Tax withholding related to net share settlements of equity awards	(53)		(53)
Issuance of common stock pursuant to employee stock purchase plan (in shares)		38
Issuance of common stock pursuant to employee stock purchase plan	806		806
Ending balance (in shares) at Jan. 31, 2021		42,854
Ending balance at Jan. 31, 2021	$ 761,014	$ 428	539,289	240,789	(19,492)
Beginning balance (in shares) at Apr. 30, 2021	43,073	43,073
Beginning balance at Apr. 30, 2021	$ 822,462	$ 431	542,737	274,535	4,759
Increase (Decrease) in Stockholders' Equity
Net income	61,202			61,202
Foreign currency translation adjustments	(8,233)				(8,233)
Other comprehensive income, net of tax	1,962				1,962
Repurchase and retirement of common stock (in shares)		(85)
Repurchase and retirement of common stock	(3,855)	$ (1)	(3,854)
Equity-based compensation	1,958		1,958
Exercise of stock options (in shares)		44
Exercise of stock options	863	$ 1	862
Vesting of restricted stock units (in shares)		8
Tax withholding related to net share settlements of equity awards	(256)		(256)
Issuance of common stock pursuant to employee stock purchase plan (in shares)		43
Issuance of common stock pursuant to employee stock purchase plan	1,140		1,140
Ending balance (in shares) at Jul. 31, 2021		43,083
Ending balance at Jul. 31, 2021	$ 877,243	$ 431	542,587	335,737	(1,512)
Beginning balance (in shares) at Apr. 30, 2021	43,073	43,073
Beginning balance at Apr. 30, 2021	$ 822,462	$ 431	542,737	274,535	4,759
Increase (Decrease) in Stockholders' Equity
Net income	196,946
Foreign currency translation adjustments	(19,304)
Other comprehensive income, net of tax	$ 9,274
Ending balance (in shares) at Jan. 31, 2022	43,095	43,095
Ending balance at Jan. 31, 2022	$ 1,003,276	$ 431	536,635	471,481	(5,271)
Beginning balance (in shares) at Jul. 31, 2021		43,083
Beginning balance at Jul. 31, 2021	877,243	$ 431	542,587	335,737	(1,512)
Increase (Decrease) in Stockholders' Equity
Net income	74,361			74,361
Foreign currency translation adjustments	4,114				4,114
Other comprehensive income, net of tax	3,289				3,289
Repurchase and retirement of common stock (in shares)		(195)
Repurchase and retirement of common stock	(9,269)	$ (2)	(9,267)
Equity-based compensation	3,215		3,215
Exercise of stock options (in shares)		52
Exercise of stock options	977	$ 1	976
Vesting of restricted stock units (in shares)		112
Vesting of restricted stock units	0	$ 1	(1)
Tax withholding related to net share settlements of equity awards	(2,579)		(2,579)
Ending balance (in shares) at Oct. 31, 2021		43,052
Ending balance at Oct. 31, 2021	951,351	$ 431	534,931	410,098	5,891
Increase (Decrease) in Stockholders' Equity
Net income	61,383			61,383
Foreign currency translation adjustments	(15,185)				(15,185)
Other comprehensive income, net of tax	4,023				4,023
Repurchase and retirement of common stock (in shares)		(87)
Repurchase and retirement of common stock	(4,734)	$ (1)	(4,733)
Equity-based compensation	3,077		3,077
Exercise of stock options (in shares)		101
Exercise of stock options	2,184	$ 1	2,183
Vesting of restricted stock units (in shares)		2
Tax withholding related to net share settlements of equity awards	(15)		(15)
Issuance of common stock pursuant to employee stock purchase plan (in shares)		27
Issuance of common stock pursuant to employee stock purchase plan	$ 1,192		1,192
Ending balance (in shares) at Jan. 31, 2022	43,095	43,095
Ending balance at Jan. 31, 2022	$ 1,003,276	$ 431	$ 536,635	$ 471,481	$ (5,271)