Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended						6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	[1]	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)	29.00%
Income tax benefit	$ 9.8	$ 1.4	$ 9.1	$ 27.7	$ 74.2		$ 101.9	$ 111.0	$ 112.4
Loss before benefit for income taxes and equity in net income of affiliates	$ 33.7	$ (1.2)	$ 24.0	$ 203.0	$ 0.6		$ 203.6	$ 227.6	$ 226.4

[1] See discussion in Note 1 - Basis of Presentation for further detail regarding the elimination of the International lag reporting.