Revisions of Previously Issued Consolidated Financial Statements - Consolidated Statements of Stockholders' Equity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021		Jun. 30, 2020
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance	$ 650.6	$ 509.9	$ 654.1		$ 541.0
Net income (loss)	10.3	(0.6)	11.9		1.2
Share-based compensation	2.6	2.3	4.0	[1]	2.8
Exercise of stock options	2.1	0.3	4.3	[2]	0.7	[2]
Share repurchases	(0.9)		(1.6)	[3]	(0.3)	[3]
Dividends and other changes in non-controlling interest					(0.4)
Other comprehensive loss	5.0	4.8	(3.0)		(28.7)
Ending balance	$ 669.7	516.3	$ 669.7		516.3
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance					541.1
Net income (loss)		(1.2)			0.0
Share-based compensation					2.8
Exercise of stock options					0.7
Share repurchases					(0.3)
Dividends and other changes in non-controlling interest					(0.4)
Other comprehensive loss		4.8			(28.7)
Ending balance		515.2			515.2
Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance					(0.1)
Net income (loss)		0.6			1.2
Share-based compensation					0.0
Exercise of stock options					0.0
Share repurchases					0.0
Dividends and other changes in non-controlling interest					0.0
Other comprehensive loss		0.0			0.0
Ending balance		$ 1.1			$ 1.1

[1] During the six months ended June 30, 2021, $0.9 million of the stock-based compensation expense is included in "Restructuring expenses and asset write offs" related to accelerated vesting of stock options, RSUs and PBUs.

[2] The par value of common shares issued may not be included in the table due to rounding. Total share amounts for common stock and treasury stock may not sum due to rounding.

[3] Relates to shares withheld for tax payments on exercise of stock options and vesting of RSUs and PBUs. Refer to Note 14, “Stock Incentive Plans”, for further information.