Income Taxes Components of Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income taxes currently (receivable) payable:
U.S. federal	$ (3.1)	$ 3.6	$ 2.3
State	(3.3)	(1.0)	0.1
Foreign	3.2	3.0	2.7
Total taxes currently (receivable) payable	(3.2)	5.6	5.1
Deferred tax (benefit) expense:
U.S. federal	(12.7)	(58.1)	(6.3)
State	7.1	(6.3)	7.9
Total deferred tax (benefit) expense	(5.6)	(64.4)	1.6
Income tax expense	$ (8.8)	$ (58.8)	$ 6.7