Income Taxes Components of Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
Federal	$ 87.1	$ 0.4	$ 0.5
Other state and local	(0.7)	0.0	0.2
Foreign	62.4	27.5	10.8
Total current	148.8	27.9	11.5
Deferred
Federal	(122.3)	31.2	26.4
Other state and local	(17.0)	0.0	0.0
Foreign	(7.0)	(0.8)	(0.8)
Total deferred	(146.3)	30.4	25.6
Total income tax expense	$ 2.5	$ 58.3	$ 37.1

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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