Basic and Diluted Earnings Per Share - Schedule of Basic and Diluted Earnings per Common Share Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023
Earnings Per Share Disclosure [Line Items]
Net income attributable to Korn Ferry	$ 246,062	$ 169,154	$ 209,529
Less: distributed and undistributed earnings to nonvested restricted stockholders	3,226	3,092	4,618
Basic net earnings attributable to common stockholders	242,836	166,062	204,911
Add: undistributed earnings to nonvested restricted stockholders	2,104	2,122	3,912
Less: reallocation of undistributed earnings to nonvested restricted stockholders	2,063	2,106	3,882
Diluted net earnings attributable to common stockholders	$ 242,877	$ 166,078	$ 204,941
Weighted-average common shares outstanding:
Basic weighted-average number of common shares outstanding (in shares)	51,778	51,038	51,482
Diluted weighted-average number of common shares outstanding (in shares)	52,806	51,432	51,883
Net earnings per common share:
Basic earnings per share (in dollars per share)	$ 4.69	$ 3.25	$ 3.98
Diluted earnings per share (in dollars per share)	$ 4.60	$ 3.23	$ 3.95
ESPP
Weighted-average common shares outstanding:
Effect of dilutive securities (in shares)	11	6	17
Restricted stock
Weighted-average common shares outstanding:
Effect of dilutive securities (in shares)	1,017	388	384