CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Treasury Stock
Balance at Dec. 31, 2018	$ 1,211.6	$ 0.9	$ 1,545.9	$ (224.2)	$ (111.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) earnings	3.2
(Loss) earnings from continuing operations	3.2
Other comprehensive (loss) earnings, net of tax	2.1
Other comprehensive loss, net of tax	2.1				2.1
Stock-based compensation expense	14.0		14.0
Common stock issued for exercise of stock options and other	1.8		1.8
Tax on restricted stock unit vesting	(5.5)		(5.5)
Balance at Jun. 30, 2019	1,227.2	0.9	1,556.2	(221.0)	(108.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0.1
Balance at Mar. 31, 2019	1,216.5	0.9	1,548.7	(226.9)	(106.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) earnings	5.9			5.9
(Loss) earnings from continuing operations	5.9
Other comprehensive (loss) earnings, net of tax	(2.7)
Other comprehensive loss, net of tax					(2.7)
Stock-based compensation expense	7.3		7.3
Common stock issued for exercise of stock options and other	0.9		0.9
Tax on restricted stock unit vesting	(0.7)		(0.7)
Balance at Jun. 30, 2019	1,227.2	0.9	1,556.2	(221.0)	(108.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(0.1)
Treasury Stock, Value	0.0
Balance at Dec. 31, 2019	1,288.5	0.9	1,574.7	(175.1)	(112.0)	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) earnings	(28.6)
(Loss) earnings from continuing operations	(32.3)			(32.3)
Other comprehensive (loss) earnings, net of tax	(4.4)
Other comprehensive loss, net of tax	(4.4)				(4.4)
Repurchase of common stock	(15.0)					(15.0)
Stock-based compensation expense	7.6		7.6
Common stock issued for exercise of stock options and other	1.7		1.7
Tax on restricted stock unit vesting	(6.0)		(6.0)
Balance at Jun. 30, 2020	1,243.8	0.9	1,578.0	(203.7)	(116.4)	(15.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0.0
Balance at Mar. 31, 2020	1,253.8	0.9	1,572.8	(184.2)	(120.7)	(15.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) earnings	(19.5)			(19.5)
(Loss) earnings from continuing operations	(19.5)			(19.5)
Other comprehensive (loss) earnings, net of tax	4.3				4.3
Other comprehensive loss, net of tax					4.3
Stock-based compensation expense	4.1		4.1
Common stock issued for exercise of stock options and other	1.3		1.3
Tax on restricted stock unit vesting	(0.2)		(0.2)
Balance at Jun. 30, 2020	1,243.8	$ 0.9	$ 1,578.0	$ (203.7)	$ (116.4)	$ (15.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(0.2)
Treasury Stock, Value	$ 15.0