Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 212.1	$ 138.0
Other comprehensive income, net of tax:
Unrealized gain on marketable securities	0.0	0.2
Unrealized foreign currency translation (loss) gain	(62.6)	155.3
Amounts reclassified out of AOCI during the year	13.2	2.0
Unrealized currency derivative contracts gain (loss)	38.3	(68.3)
Total other comprehensive income (loss) for the year	(11.1)	89.2
Comprehensive income	201.0	227.2
Comprehensive income attributable to noncontrolling interests	(65.4)	(124.2)
Comprehensive income attributable to Kennedy-Wilson Holdings, Inc.	135.6	103.0
Foreign Exchange Contract [Member]
Other comprehensive income, net of tax:
Unrealized currency derivative contracts gain (loss)	38.3	(68.3)
Interest Rate Swap [Member]
Other comprehensive income, net of tax:
Unrealized currency derivative contracts gain (loss)	$ 0.0	$ 0.0