Business Combination Business Combinatinos (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 03, 2014
Business Acquisition [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 253.3		$ 834.8
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		9.2		11.2
Business Acquisition, Transaction Costs		$ 14.7		14.7
Payments to Acquire Businesses, Net of Cash Acquired	$ 802.6		$ 0.0	802.6	$ 16.4
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	0.7
Senior Notes						$ 230.0
Goodwill, Acquired During Period			1.0	277.5
Interest Payable, Current						13.0
Interest Paid			15.0	$ 16.6	$ 11.2
Business Acquisition, Effective Date of Acquisition				Mar. 03, 2014
2014 Term Loan [Member]
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						350.0
2014 Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 300.0			$ 300.0
Convertible Debt [Member]
Business Acquisition [Line Items]
Repayments of Convertible Debt	$ 16.1
Interest Paid	3.2
Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Interest Paid	0.3
Repayments of Lines of Credit	$ 63.1