Segments - Schedule of Reconciliation of the Company's Segment Operating Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Total operating income (loss)	$ (62.0)	$ 16.9	$ 24.1	$ 1.7	$ 8.5	$ 9.8	$ 11.9	$ (21.8)	$ (19.3)	$ 8.4	$ (143.0)
Asset impairment expense									82.6	0.1	96.9
Restructuring expense									12.9	27.2	23.4
Segment Operating Income (Loss)
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Total operating income (loss)									22.1	45.0	(27.9)
Corporate
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Total operating income (loss)									(37.5)	(33.0)	(35.8)
Reconciliation of Company’s Segment Operating Income (Loss)
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Total operating income (loss)									(19.3)	8.4	(143.0)
Asset impairment expense											(77.3)
Restructuring expense									$ (3.9)	$ (3.6)	$ (2.0)