Basic and Diluted (Loss) Earnings Per Share - Basic and Diluted Earnings per Common Share Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022
Earnings Per Share Disclosure [Line Items]
Net (loss) income attributable to Korn Ferry	$ (1,711)	$ 73,541	$ 44,894	$ 150,788
Less: distributed and undistributed earnings to nonvested restricted stockholders	169	1,615	843	3,295
Basic net (loss) earnings attributable to common stockholders	(1,880)	71,926	44,051	147,493
Add: undistributed earnings to nonvested restricted stockholders	0	1,436	459	2,945
Less: reallocation of undistributed earnings to nonvested restricted stockholders	0	1,432	457	2,927
Diluted net (loss) earnings attributable to common stockholders	$ (1,880)	$ 71,930	$ 44,053	$ 147,511
Basic weighted-average number of common shares outstanding (in shares)	51,328	51,868	51,131	51,820
Diluted weighted-average number of common shares outstanding (in shares)	51,328	52,005	51,401	52,143
Basic (loss) earnings per share (in usd per share)	$ (0.04)	$ 1.39	$ 0.86	$ 2.85
Diluted (loss) earnings per share (in usd per share)	$ (0.04)	$ 1.38	$ 0.86	$ 2.83
ESPP
Earnings Per Share Disclosure [Line Items]
Effect of dilutive securities (in shares)	0	3	8	4
Restricted Stock Awards
Earnings Per Share Disclosure [Line Items]
Effect of dilutive securities (in shares)	0	134	262	319