CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' DEFICIT - USD ($) $ in Millions		Common Stock		Treasury Stock at Cost	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Deficit	Cumulative Effect, Period of Adoption, Adjustment	Total
Balances at beginning of period at Dec. 31, 2017		$ 0.9		$ (4.8)	$ 299.9		$ 9.1	$ (432.6)	$ 9.1	$ (136.6)
Balances at beginning of period (in shares) at Dec. 31, 2017		88,426,742
Increase (Decrease) in Stockholders' Deficit
Changes in accumulated other comprehensive loss						$ (6.5)				(6.5)
Stock-based compensation					13.0					13.0
Issuance of restricted stock, net (in shares)		1,684,778
Purchase of shares				(73.3)						$ (73.3)
Purchase of shares (in shares)		(7,431,140)								(7,431,140)
Other					(0.2)					$ (0.2)
Net income (loss)								(87.3)		(87.3)
Balances at end of period at Dec. 31, 2018	[1]	$ 0.9		(78.1)	312.7	(6.5)		(510.8)		(281.8)
Balances at end of period (in shares) at Dec. 31, 2018	[1]	82,680,380
Increase (Decrease) in Stockholders' Deficit
Changes in accumulated other comprehensive loss						(9.0)				(9.0)
Stock-based compensation					10.1					10.1
Issuance of restricted stock, net (in shares)		1,609,514
Purchase of shares				(1.6)						$ (1.6)
Purchase of shares (in shares)		(186,786)								(186,786)
Net income (loss)								36.4		$ 36.4
Balances at end of period at Dec. 31, 2019	[1]	$ 0.9		(79.7)	322.8	(15.5)		(474.4)		$ (245.9)
Balances at end of period (in shares) at Dec. 31, 2019		84,103,108	[1]							84,103,108
Increase (Decrease) in Stockholders' Deficit
Changes in accumulated other comprehensive loss						9.0				$ 9.0
Stock-based compensation		$ 0.1			11.0					11.1
Issuance of restricted stock, net (in shares)		3,004,954
Purchase of shares				(1.0)						$ (1.0)
Purchase of shares (in shares)		(260,265)								(260,265)
Net income (loss)								14.4		$ 14.4
Balances at end of period at Dec. 31, 2020	[1]	$ 1.0		$ (80.7)	$ 333.8	$ (6.5)		$ (460.0)		$ (212.4)
Balances at end of period (in shares) at Dec. 31, 2020		86,847,797	[1]							86,847,797

[1] Included in outstanding shares as of December 31, 2020, 2019 and 2018 are 4,990,971, 3,140,168 and 2,356,418, respectively, of non-vested shares of restricted stock awards granted to employees and directors.