Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss	Noncontrolling Interest
Shares outstanding, beginning (in shares) at Dec. 31, 2019			39.7
Shareholders' equity, beginning at Dec. 31, 2019	$ 511.0		$ 0.0	$ 509.2		$ (0.9)	$ 2.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Net income	$ (23.5)			(23.4)			(0.1)
Repurchase of common stock (in shares)			(0.3)
Repurchase of common stock	(27.9)		$ (4.3)	(23.6)
Cash settlement of stock awards	12.7			12.7
Taxes paid related to net share settlement of stock awards	(15.1)			(15.1)
Stock-based compensation	4.3		$ 4.3
Shares outstanding, ending (in shares) at Mar. 31, 2020			39.4
Shareholders' equity, ending at Mar. 31, 2020	435.6	$ (0.5)	$ 0.0	433.9	$ (0.5)	(0.9)	2.6
Shares outstanding, beginning (in shares) at Dec. 31, 2020			39.5
Shareholders' equity, beginning at Dec. 31, 2020	367.1		$ 18.2	349.8		(0.9)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	36.1			36.1
Issuance of common stock (in shares)			0.1
Issuance of common stock	0.0
Repurchase of common stock (in shares)			(1.0)
Repurchase of common stock	(193.9)		$ (22.0)	(171.9)
Taxes paid related to net share settlement of stock awards (in shares)			(0.1)
Taxes paid related to net share settlement of stock awards	(12.6)			(12.6)
Stock-based compensation	5.5		$ 5.5
Shares outstanding, ending (in shares) at Mar. 31, 2021			38.5
Shareholders' equity, ending at Mar. 31, 2021	$ 202.2		$ 1.7	$ 201.4		$ (0.9)	$ 0.0