EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net income (loss) attributable to Kennedy-Wilson Holdings, Inc. common shareholders
Net income attributable to Kennedy-Wilson Holdings, Inc. common shareholders	$ 64.8	$ 313.2	$ 92.9
Weighted average shares outstanding for basic (in shares)	136,900,875	138,552,058	139,741,411
Basic earnings (loss) per share (in dollars per share)	$ 0.47	$ 2.26	$ 0.66
Weighted average shares outstanding for diluted (in shares)	138,567,534	140,132,435	140,347,365
Income per diluted (in dollars per share)	$ 0.47	$ 2.24	$ 0.66
Potentially dilutive securities (in shares)	26,958,511	13,572,590	13,236,896