Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating expenses				$ (0.7)
Loss from discontinued operations before income taxes	$ 0.0	$ 0.0	$ 0.0	(0.7)
Gain from disposal of discontinued operations	0.0	0.0	0.0	49.2
Income tax expense for discontinued operations	0.0	0.0	0.0	18.9
Net income from discontinued operations	$ 0.0	$ 0.0	$ 0.0	29.6
Cash flows from operating activities for discontinued operations				(0.7)
Cash flows from investing activities for discontinued operations				$ 75.5