Basic and Diluted 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		9 Months Ended
	Jan. 31, 2023	Jan. 31, 2022	Jan. 31, 2023	Jan. 31, 2022
Earnings Per Share Disclosure [Line Items]
Net income attributable to Korn Ferry	$ 11,247	$ 84,101	$ 162,035	$ 234,696
Less: distributed and undistributed earnings to nonvested restricted stockholders	249	1,798	3,545	5,363
Basic net earnings attributable to common stockholders	10,998	82,303	158,490	229,333
Add: undistributed earnings to nonvested restricted stockholders	72	1,658	3,017	4,908
Less: reallocation of undistributed earnings to nonvested restricted stockholders	72	1,643	2,997	4,856
Diluted net earnings attributable to common stockholders	$ 10,998	$ 82,318	$ 158,510	$ 229,385
Basic weighted-average number of common shares outstanding (in shares)	51,278	52,999	51,639	52,958
Diluted weighted-average number of common shares outstanding (in shares)	51,431	53,495	51,999	53,538
Basic earnings per share (in usd per share)	$ 0.21	$ 1.55	$ 3.07	$ 4.33
Diluted earnings per share (in usd per share)	$ 0.21	$ 1.54	$ 3.05	$ 4.28
ESPP
Earnings Per Share Disclosure [Line Items]
Effect of dilutive securities (in shares)	3	6	8	7
Restricted stock
Earnings Per Share Disclosure [Line Items]
Effect of dilutive securities (in shares)	150	490	352	573