Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net (loss) income	$ (19.7)	$ 19.4	$ (64.7)	$ 162.2
Other comprehensive income (loss), net of tax:
Unrealized foreign currency translation gain (loss)	28.8	(31.7)	33.5	(36.4)
Amounts reclassified out of AOCI during the period	0.0	0.0	0.2	9.8
Total other comprehensive income (loss) for the period	10.6	(8.3)	2.9	13.9
Comprehensive (loss) income	(9.1)	11.1	(61.8)	176.1
Comprehensive (income) loss attributable to noncontrolling interests	(1.9)	2.3	1.1	(105.0)
Comprehensive income (loss) attributable to Kennedy-Wilson Holdings, Inc.	(11.0)	13.4	(60.7)	71.1
Foreign Exchange Contract [Member]
Other comprehensive income (loss), net of tax:
Unrealized gain (loss)	(18.6)	24.9	(24.9)	42.4
Interest Rate Swap [Member]
Other comprehensive income (loss), net of tax:
Unrealized gain (loss)	$ 0.4	$ (1.5)	$ (5.9)	$ (1.9)