Goodwill and Other Intangible Assets Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill acquired	$ 70.0	$ 55.3
Year to date amortization expense	32.3	$ 28.2	$ 23.8
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Amortization expense, 2017	32.4
Amortization expense, 2018	31.2
Amortization expense, 2019	29.5
Amortization expense, 2020	28.2
Amortization expense, 2021	$ 27.3