Business Combinations Business Combinations - Table 11 (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2014	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
Encompass [Member]
Business Acquisition [Line Items]
Cash Acquired from Acquisition		$ 20.9
Net Cash Paid For All Acquisitions During Each Period Presented
Fair value of assets acquired			260.1
Goodwill	$ 34.0		592.5
Fair value of liabilities assumed			113.5
Redeemable noncontrolling interests			(64.5)
Net cash paid for acquisitions			$ 674.6