Condensed Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net (loss) income	$ (80.0)	$ 41.7
Other comprehensive loss, net of tax:
Foreign currency translation adjustments, net	(9.0)	(8.3)
Unrealized losses on derivative contracts, net	(17.9)	(3.3)
Amortization of prior service costs and actuarial losses, net	9.2	5.7
Total other comprehensive (loss) income, net of tax	(17.7)	(5.9)
Comprehensive (loss) income	$ (97.7)	$ 35.8