Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases
Maximum risk for lease	$ 19.5
Future rental payments required under total noncancelable operating leases
2016	33.1
2017	26.5
2018	21.1
2019	16.2
2020	10.1
Thereafter	44.7
Lease expense for all operating leases	$ 65.6	$ 81.2	$ 73.2