Restructuring Charges 2020 Plan Restructuring Activity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Severance and termination costs	$ 0.0	$ 0.6	$ 0.3	$ 2.1
Lease impairment costs	0.0	(0.9)	5.3	(1.1)
Other restructuring costs	(0.1)	0.1	0.9	0.1
Restructuring charges	(0.1)	$ (0.2)	6.5	$ 1.1
Restructuring Reserve	3.5		3.5		$ 9.4
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	3.5		3.5		9.4
Lease impairment costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0.0		0.0		0.0
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0.0		0.0		$ 0.0
Non-cash Items [Member]
Restructuring Cost and Reserve [Line Items]
Severance and termination costs			0.0
Lease impairment costs			5.3
Other restructuring costs			0.9
Restructuring charges			6.2
Cash Payments [Member]
Restructuring Cost and Reserve [Line Items]
Severance and termination costs			6.2
Lease impairment costs			0.0
Other restructuring costs			0.0
Restructuring charges			$ 6.2