Discontinued Operations - Financial Results (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (Loss) from Discontinued Operations, Net of Taxes	$ 0.0		$ 7.9	$ (2.2)	$ 15.9
(Loss) Gain on Sale of Discontinued Operations, Net of Taxes	(0.3)		0.0	3.3	0.0
Discontinued Operations, Net of Taxes	(0.3)		7.9	1.1	15.9
ASC [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	0.0		61.9	27.2	135.5
Operating expense	0.0		44.5	22.5	96.8
Depreciation expense	0.0		3.6	1.7	7.1
Selling, general and administrative expense	0.0		1.8	2.8	6.0
Total Expenses	0.0		49.9	27.0	109.9
Other expense	0.0		(1.7)	(3.0)	(4.9)
Income (Loss) from Discontinued Operations Before Taxes	0.0		10.3	(2.8)	20.7
Income tax (expense) benefit	0.0		(2.4)	0.6	(4.8)
Income (Loss) from Discontinued Operations, Net of Taxes	0.0		7.9	(2.2)	15.9
(Loss) Gain on Sale of Discontinued Operations, Net of Taxes	(0.3)	$ 3.6	0.0	3.3	0.0
Discontinued Operations, Net of Taxes	$ (0.3)		$ 7.9	$ 1.1	$ 15.9