Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital (Deficit)	Retained Earnings	Net Parent Company Investment	Accumulated Other Comprehensive (Loss) Income	Treasury Stock
Common stock, outstanding beginning of period (in shares) at Dec. 31, 2014		0
Beginning balance at Dec. 31, 2014	$ 1,255.3	$ 0.0	$ 0.0	$ 0.0	$ 1,276.0	$ (20.7)	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	156.1				156.1
Other comprehensive income	(23.8)					(23.8)
Net decrease in parent company investment	(176.0)				(176.0)
Common stock, outstanding end of period (in shares) at Dec. 31, 2015		0
Ending balance at Dec. 31, 2015	1,211.6	$ 0.0	0.0	0.0	1,256.1	(44.5)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	71.5			56.2	15.3
Other comprehensive income	1.1					1.1
Net decrease in parent company investment	(1,362.0)				(1,362.0)
Separation related adjustments	(1.0)				(1.0)
Reclassification of net investment to additional paid-in capital (As Restated)	0.0		(91.6)		91.6
Issuance of common stock at Spin-Off (in shares)		137,016,712
Issuance of common stock at Spin-Off	0.0	$ 1.4	(1.4)
Issuance of common stock, equity-based compensation plans (in shares)		1,584,615
Issuance of common stock, stock-based compensation plans	16.2		16.2
Stock-based compensation expense	6.3		6.3
Adjustments in connection with the Spin-Off (As Restated)	$ (0.1)		(0.1)	0.0
Common stock, outstanding end of period (in shares) at Dec. 31, 2016	138,562,016	138,601,327
Ending balance at Dec. 31, 2016	$ (56.4)	$ 1.4	(70.6)	56.2	0.0	(43.4)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	132.9
Other comprehensive income	11.4					11.4
Issuance of common stock, equity-based compensation plans (in shares)		890,533
Issuance of common stock, stock-based compensation plans	4.8		4.8
Stock-based compensation expense	11.1		11.1
Value of shares in deferred compensation plan	$ (0.2)						(0.2)
Common stock, outstanding end of period (in shares) at Dec. 31, 2017	139,440,470	139,491,860.00000
Ending balance at Dec. 31, 2017	$ 103.6	$ 1.4	$ (54.7)	$ 189.1	$ 0.0	$ (32.0)	$ (0.2)