Consolidated Statements of Comprehensive Income (loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net income (loss)	$ 29.0	$ (62.3)
Net pension adjustments, net of tax:
Reclassification of adjustments for defined benefit plans recorded in net loss		20.6
Total net pension adjustments		20.6
Total other comprehensive income, net of tax		20.6
Comprehensive income (loss)	$ 29.0	$ (41.7)