Consolidated Statements of Equity - USD ($) $ in Millions	Total	Foreign Exchange Contract	Interest Rate Swap	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Foreign Exchange Contract	Accumulated Other Comprehensive Loss Interest Rate Swap	Noncontrolling Interests
Beginning balance outstanding (in shares) at Dec. 31, 2019				300,000	142,283,109
Balance at beginning of period at Dec. 31, 2019	$ 1,719.2			$ 295.2	$ 0.0	$ 1,754.5	$ 46.2	$ (417.2)			$ 40.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares forfeited (in shares)					(62,710)
Restricted stock grants (RSG) (in shares)					2,543,551
Shares retired due to RSG vesting (in shares)					(571,983)
Shares retired due to RSG vesting	(11.6)					(11.6)
Shares retired due to common stock repurchase program (in shares)					(2,826,644)
Shares retired due to common stock repurchase program	(45.8)					(50.0)	4.2
Stock based compensation	32.3					32.3
Other comprehensive (loss) income:
Unrealized foreign currency translation gain (loss), net of tax	66.7							66.1			0.6
Unrealized currency derivative contracts gain (loss)		$ (37.8)	$ (4.7)						$ (37.8)	$ (4.7)
Common stock dividends	(125.6)						(125.6)
Preferred stock dividends	(17.2)						(17.2)
Net income	107.8						110.1				(2.3)
Contributions from noncontrolling interests	4.5										4.5
Distributions to noncontrolling interests	(18.9)										(18.9)
KW Europe II deconsolidation	3.8										3.8
Ending balance outstanding (in shares) at Dec. 31, 2020				300,000	141,365,323
Balance at end of period at Dec. 31, 2020	1,672.7			$ 295.2	$ 0.0	1,725.2	17.7	(393.6)			28.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares forfeited (in shares)					(237,588)
Restricted stock grants (RSG) (in shares)					619,945
Shares retired due to RSG vesting (in shares)					(967,536)
Shares retired due to RSG vesting	(20.5)					(20.5)
Shares retired due to common stock repurchase program (in shares)					(2,824,665)
Shares retired due to common stock repurchase program	(62.7)				$ (62.7)	(50.0)	(12.7)
Stock based compensation	28.7					28.7
Other comprehensive (loss) income:
Unrealized foreign currency translation gain (loss), net of tax	(56.6)							(55.8)			(0.8)
Unrealized currency derivative contracts gain (loss)		56.1	3.7						56.1	3.7
Common stock dividends	(125.8)						(125.8)
Preferred stock dividends	(17.2)						(17.2)
Net income	336.4						330.4				6.0
Contributions from noncontrolling interests	7.8										7.8
Distributions to noncontrolling interests	(18.7)										(18.7)
Incentive allocations to noncontrolling interests	0.0					(3.8)					3.8
Ending balance outstanding (in shares) at Dec. 31, 2021				300,000	137,955,479
Balance at end of period at Dec. 31, 2021	1,803.9			$ 295.2	$ 0.0	1,679.6	192.4	(389.6)			26.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock grants (RSG) (in shares)					1,221,362
Shares retired due to RSG vesting (in shares)					(834,911)
Shares retired due to RSG vesting	(18.6)					(18.6)
Shares retired due to common stock repurchase program (in shares)					(551,162)
Shares retired due to common stock repurchase program	(12.6)					(9.8)	(2.8)
Stock based compensation					$ 29.0	29.0
Other comprehensive (loss) income:
Unrealized foreign currency translation gain (loss), net of tax	(71.7)							(68.7)			(3.0)
Unrealized currency derivative contracts gain (loss)		$ 23.4	$ 4.8						$ 23.4	$ 4.8
Common stock dividends	(132.3)						(132.3)
Preferred stock dividends	(28.9)						(28.9)
Net income	101.9						93.7				8.2
Contributions from noncontrolling interests	25.7										25.7
Distributions to noncontrolling interests	(10.8)										(10.8)
Ending balance outstanding (in shares) at Dec. 31, 2022				600,000	137,790,768
Balance at end of period at Dec. 31, 2022	$ 2,010.4			$ 592.5	$ 0.0	$ 1,679.5	$ 122.1	$ (430.1)			$ 46.4