Employee Retirement Plans (Details 4) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]
Actuarial gain (loss)	$ (9.4)	$ (71.9)	$ 83.7
Amortization of actuarial loss	5.0	2.1	4.9
Amortization of prior service cost	0.0	0.0	0.1
Curtailment	0.0	0.1	0.0
Total before income taxes	(4.4)	(69.7)	88.7
Income tax expense (benefit)	(1.6)	(25.9)	32.9
Net amount recognized in other comprehensive income (loss)	$ (2.8)	$ (43.8)	$ 55.8