Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss)	(Accumulated Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)		25,832,193
Beginning balance at Dec. 31, 2018	$ 391.0	$ 0.0	$ (39.7)	$ 678.6	$ (61.6)	$ (186.3)
Beginning balance (in shares) at Dec. 31, 2018			2,452,165
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	(16.7)					(16.7)
Stock-based employee compensation, net	0.4		$ 0.9	(0.5)
Stock-based employee compensation, net (in shares)		53,908	(50,251)
Other comprehensive income (loss)	2.9				2.9
Ending balance at Mar. 31, 2019	377.6	$ 0.0	$ (38.8)	678.1	(58.7)	(203.0)
Ending balance (in shares) at Mar. 31, 2019		25,886,101	2,401,914
Beginning balance at Dec. 31, 2018	391.0	$ 0.0	$ (39.7)	678.6	(61.6)	(186.3)
Beginning balance (in shares) at Dec. 31, 2018			2,452,165
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	(2.0)
Other comprehensive income (loss)	0.4				0.4
Ending balance at Jun. 30, 2019	339.5	0.0	$ (89.2)	678.2	(61.2)	(188.3)
Ending balance (in shares) at Jun. 30, 2019			6,857,288
Beginning balance at Mar. 31, 2019	377.6	$ 0.0	$ (38.8)	678.1	(58.7)	(203.0)
Beginning balance (in shares) at Mar. 31, 2019		25,886,101	2,401,914
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	14.7					14.7
Stock repurchased during period, (in shares)		(4,504,504)
Shares, repurchased amount			4,504,504
Common stock repurchased	(51.3)		$ (51.3)
Stock-based employee compensation, net	1.0		$ 0.9	0.1
Stock-based employee compensation, net (in shares)		93,305	(49,130)
Other comprehensive income (loss)	(2.5)				(2.5)
Ending balance at Jun. 30, 2019	$ 339.5	$ 0.0	$ (89.2)	678.2	(61.2)	(188.3)
Ending balance (in shares) at Jun. 30, 2019			6,857,288
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)		21,474,902
Common stock, outstanding (in shares)	21,519,761	21,519,761
Beginning balance at Dec. 31, 2019	$ 268.3	$ 0.0	$ (88.9)	676.7	(74.7)	(244.8)
Beginning balance (in shares) at Dec. 31, 2019			6,837,897
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	(13.2)					(13.2)
Stock-based employee compensation, net	0.7	$ 0.0	$ 0.7	0.0
Stock-based employee compensation, net (in shares)		36,072	(36,072)
Other comprehensive income (loss)	0.1				0.1
Ending balance at Mar. 31, 2020	255.9	$ 0.0	$ (88.2)	676.7	(74.6)	(258.0)
Ending balance (in shares) at Mar. 31, 2020		21,555,833	6,801,825
Beginning balance at Dec. 31, 2019	268.3	$ 0.0	$ (88.9)	676.7	(74.7)	(244.8)
Beginning balance (in shares) at Dec. 31, 2019			6,837,897
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	(19.5)
Other comprehensive income (loss)	1.7				1.7
Ending balance at Jun. 30, 2020	251.8	0.0	$ (87.9)	677.0	(73.0)	(264.3)
Ending balance (in shares) at Jun. 30, 2020			6,783,140
Beginning balance at Mar. 31, 2020	255.9	$ 0.0	$ (88.2)	676.7	(74.6)	(258.0)
Beginning balance (in shares) at Mar. 31, 2020		21,555,833	6,801,825
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)	(6.3)					(6.3)
Stock-based employee compensation, net	0.6	$ 0.0	$ 0.3	0.3
Stock-based employee compensation, net (in shares)		37,689	(18,685)
Other comprehensive income (loss)	1.6				1.6
Ending balance at Jun. 30, 2020	$ 251.8	$ 0.0	$ (87.9)	$ 677.0	$ (73.0)	$ (264.3)
Ending balance (in shares) at Jun. 30, 2020			6,783,140
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, outstanding (in shares)	21,593,522	21,593,522