Basic and Diluted Earnings Per Share - Schedule of Basic and Diluted Earnings per Common Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jul. 31, 2025	Jul. 31, 2024
Earnings Per Share Disclosure [Line Items]
Net income attributable to Korn Ferry	$ 66,636	$ 62,604
Less: distributed and undistributed earnings to nonvested restricted stockholders	855	1,006
Basic net earnings attributable to common stockholders	65,781	61,598
Add: undistributed earnings to nonvested restricted stockholders	470	658
Less: reallocation of undistributed earnings to nonvested restricted stockholders	462	648
Diluted net earnings attributable to common stockholders	$ 65,789	$ 61,608
Weighted-average common shares outstanding:
Basic weighted-average number of common shares outstanding (in shares)	51,466	51,950
Diluted weighted-average number of common shares outstanding (in shares)	52,368	52,745
Net earnings per common share:
Basic earnings per share (in usd per share)	$ 1.28	$ 1.19
Diluted earnings per share (in usd per share)	$ 1.26	$ 1.17
ESPP
Weighted-average common shares outstanding:
Effect of dilutive securities (in shares)	3	0
Restricted Stock
Weighted-average common shares outstanding:
Effect of dilutive securities (in shares)	899	795