Acquisitions - Additional Disclosures (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Revenues	$ 1,109.9	$ 1,137.6	$ 1,094.7	$ 1,061.5	$ 1,057.2	$ 1,103.7	$ 1,103.2	$ 1,034.0	$ 4,403.7	$ 4,298.1	$ 4,160.2
Income (Loss) from Operations	84.2	$ 95.4	$ 87.6	$ 75.5	$ 78.1	$ 105.1	$ 105.6	$ 107.2	342.7	396.0	427.1
Payments to Acquire Businesses, Net of Cash Acquired									189.4	332.7	163.2
Acquisition of Business											$ 163.2
2017 Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets acquired and Liabilities Assumed, Pension and Postretirement Benefits	$ 0.5								0.5
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Pension and Postretirement Benefits									$ 0.0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life									18 years
Revenues									$ 44.5
Income (Loss) from Operations									1.5
Payments to Acquire Businesses, Net of Cash Acquired									189.0
Acquisition of Business									192.5
Total Purchase Consideration									206.5
2016 Acquisitions [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired										$ 333.0
Scenario, Previously Reported [Member] | 2017 Acquisitions [Member]
Business Acquisition [Line Items]
Acquisition of Business									191.0
Total Purchase Consideration									$ 205.0