Business Combinations - Table 13 (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Cash Paid For All Acquisitions During Each Period Presented
Goodwill	$ 806.1	$ 593.1	$ 13.7
Net cash paid for acquisitions	985.1	694.8	28.9
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Cash Acquired from Acquisition	$ 5.1
Net Cash Paid For All Acquisitions During Each Period Presented
Fair value of assets acquired		60.1	15.6
Goodwill		34.6	13.7
Fair value of liabilities assumed		21.2	0.4
Fair value of noncontrolling interest owned by joint venture partner		(18.3)	0.0
Fair value of equity interest prior to acquisition		35.0	0.0
Net cash paid for acquisitions		$ 20.2	$ 28.9