Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (46.0)	$ (4.6)	$ (68.0)	$ (7.6)
Other comprehensive income (loss), net of tax:
Foreign currency translation (loss) gain	(3.1)	1.6	(1.3)	2.6
Cash flow hedges:
Unrealized (loss) gain on cash flow hedges arising during the period, net of tax of $0.0, $0.2	0.0	(0.1)	0.0	0.5
Reclassification adjustment for net losses included in net income, net of tax of $0.6, $1.1	0.0	1.7	0.0	3.5
Defined benefit plans:
Net (loss) gain arising from remeasurement during the period, net of tax of ($0.4), $1.8, ($0.4), $1.8	(1.3)	6.0	(1.3)	6.0
Amortization of prior service benefits included in net income, net of tax of ($0.2), ($0.3)	0.0	(0.5)	0.0	(1.0)
Amortization of net actuarial loss included in net income, net of tax of $1.2, $2.6	0.0	4.0	0.0	8.9
Total other comprehensive (loss) income	(4.4)	12.7	(2.6)	20.5
Total comprehensive (loss) income	$ (50.4)	$ 8.1	$ (70.6)	$ 12.9