Consolidated and Combined Statements of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Additional Paid-In Capital	Additional Paid-In Capital Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjusted Balance	Former Parent’s Investment	Former Parent’s Investment Cumulative Effect, Period of Adoption, Adjustment	Former Parent’s Investment Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Cumulative Effect, Period of Adoption, Adjusted Balance	Noncontrolling Interests	Noncontrolling Interests Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning balance (in shares) at Dec. 31, 2017				0
Beginning balance at Dec. 31, 2017	$ 1,738.8			$ 0.0		$ 0.0		$ 0.0		$ 1,576.1			$ 158.8		$ 3.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	385.5									385.5
Net transfers to Former Parent	(311.9)									(311.9)
Other comprehensive income (loss)	(32.5)												(32.5)
Stock-based compensation expense	13.8									13.8
Change in noncontrolling interests	$ (0.8)														(0.8)
Exercise of common stock options and stock award distributions, net of shares for tax withholding (in shares)	292,000
Ending balance (in shares) at Dec. 31, 2018				0
Ending balance at Dec. 31, 2018	$ 1,792.9			$ 0.0		0.0		0.0		1,663.5			126.3		3.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	436.5									436.5
Net transfers to Former Parent	(299.4)									(299.4)
Non-cash settlement of related-party borrowings	(151.2)									(151.2)
Other comprehensive income (loss)	22.4												22.4
Stock-based compensation expense	13.1									13.1
Change in noncontrolling interests	$ 1.8														1.8
Exercise of common stock options and stock award distributions, net of shares for tax withholding (in shares)	335,000
Ending balance (in shares) at Dec. 31, 2019	1,000			0	0
Ending balance at Dec. 31, 2019	$ 1,816.1	$ (16.9)	$ 1,799.2	$ 0.0	$ 0.0	0.0	$ 0.0	0.0	$ 0.0	1,662.5	$ (16.9)	$ 1,645.6	148.7	$ 148.7	4.9	$ 4.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	342.0							131.1		210.9
Net transfers to Former Parent	(382.7)							(144.7)		(238.0)
Other comprehensive income (loss)	45.1												45.1
Stock-based compensation expense	22.5					6.0				16.5
Change in noncontrolling interests	(1.0)														(1.0)
Recapitalization (in shares)				168,400,000
Consideration to Former Parent in connection with the Separation	$ (1,635.0)									(1,635.0)
Exercise of common stock options and stock award distributions, net of shares for tax withholding (in shares)	360,000			100,000
Exercise of common stock options and stock award distributions, net of shares for tax withholding	$ 1.6					1.6
Ending balance (in shares) at Dec. 31, 2020	168,497,098			168,500,000
Ending balance at Dec. 31, 2020	$ 191.7			$ 0.0		$ 7.6		$ (13.6)		$ 0.0			$ 193.8		$ 3.9