Income Taxes Schedule of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Federal income tax provision (benefit)
Current	$ (32.2)	$ (71.3)	$ 2.1
Deferred	55.7	(257.8)	(339.8)
State income tax provision (benefit)
Current	(15.1)	1.5	0.5
Deferred	(51.4)	10.2	25.0
Total income tax provision (benefit)	$ (43.0)	$ (317.4)	$ (312.2)