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Segment Reporting Income (Loss) From Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Sep. 30, 2019	Mar. 31, 2019
Segment Reporting
Income (loss) before income taxes	$ (158.7)		$ 181.3
Other income (expense), net	(4.8)		23.9
North America [Member]
Segment Reporting
Income (loss) before income taxes	76.2		245.9
CANADA
Segment Reporting
Impairments		$ 668.3
Europe [Member]
Segment Reporting
Income (loss) before income taxes	(76.8)		(38.4)
Unallocated [Member]
Segment Reporting
Income (loss) before income taxes	(158.1)		(26.2)
Unrealized Gain (Loss) on Commodity Contracts	$ (99.1)		34.1
Purchase Price Adjustment [Member] \| Affiliated Entity [Member]
Segment Reporting
Other income (expense), net			$ 1.5