Condensed Consolidated Statements of Member's Interest - USD ($) $ in Millions	3 Months Ended		24 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 2,856.6	$ 2,745.3
Net (Loss) Income	(23.5)	95.3
Other Comprehensive (Loss) Income, Net of Tax:
Derivative Instruments	(1.7)	(0.6)
Pension and Postretirement Benefit Plans	194.0	1.9
Currency Translation Adjustment	(57.0)	4.8
Distribution of Membership Interest, Net	(397.3)	(88.7)	$ (247.9)
Ending balance	2,571.1	2,758.0	2,856.6
Member's Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	3,236.8	3,142.6
Net (Loss) Income	(23.5)	95.3
Other Comprehensive (Loss) Income, Net of Tax:
Distribution of Membership Interest, Net	(397.3)	(88.7)
Ending balance	2,816.0	3,149.2	3,236.8
Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(380.2)	(397.3)
Other Comprehensive (Loss) Income, Net of Tax:
Derivative Instruments	(1.7)	(0.6)
Pension and Postretirement Benefit Plans	194.0	1.9
Currency Translation Adjustment	(57.0)	4.8
Ending balance	$ (244.9)	$ (391.2)	$ (380.2)