Consolidated Statements of Stockholders' Equity (Deficit) (unaudited) - USD ($) $ in Millions	Total	Previously Reported	Common Stock	Common Stock Previously Reported	Treasury Stock	Treasury Stock Previously Reported	Additional Paid-In Capital	Additional Paid-In Capital Previously Reported	Accumulated Deficit	Accumulated Deficit Previously Reported	Accumulated Other Comprehensive (Loss)	Accumulated Other Comprehensive (Loss) Previously Reported
Beginning Balance (in shares) at Dec. 31, 2018			123,353,656		12,811,755
Beginning Balance at Dec. 31, 2018	$ 6.3		$ 1.2		$ (62.6)		$ 361.0		$ (289.8)		$ (3.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	4.5						4.5
Issuance of common stock related to share-based compensation plans (in shares)			2,613
Exercise of vested stock options (in shares)			145,235
Exercise of vested stock options	0.4						0.4
Dividends paid/accrued	(5.0)						(5.0)
Acquisition of treasury stock related to share-based compensation plans (in shares)					(342,998)
Acquisition of treasury stock related to share-based compensation plans	(3.3)				$ (3.3)
Forfeitures (in shares)					(1,208)
Net change on derivatives designated as cash flow hedges, net of tax	0.2										0.2
Foreign currency translation adjustments	0.5										0.5
Net income (loss)	0.2								0.2
Ending Balance (in shares) at Mar. 31, 2019			123,501,504		13,155,961
Ending Balance at Mar. 31, 2019	3.8		$ 1.2		$ (65.9)		360.9		(289.6)		(2.8)
Beginning Balance (in shares) at Dec. 31, 2019				127,807,546		13,786,266
Beginning Balance at Dec. 31, 2019	18.1	$ 18.1		$ 1.3		$ (73.6)		$ 372.7		$ (277.8)		$ (4.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	$ 4.8						4.8
Issuance of common stock related to share-based compensation plans (in shares)			1,720
Exercise of vested stock options (in shares)	553,520		553,520
Exercise of vested stock options	$ 3.1						3.1
Dividends paid/accrued	(5.4)						(5.4)
Acquisition of treasury stock related to share-based compensation plans (in shares)					(545)
Acquisition of treasury stock related to share-based compensation plans	0.0				$ 0.0
Net change on derivatives designated as cash flow hedges, net of tax	(4.4)										(4.4)
Foreign currency translation adjustments	(2.1)										(2.1)
Net income (loss)	18.2								18.2
Ending Balance (in shares) at Mar. 31, 2020			128,362,786		13,786,811
Ending Balance at Mar. 31, 2020	$ 31.5		$ 1.3		$ (73.6)		$ 375.2		$ (260.4)		$ (11.0)