Business Combinations (Narratives) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Apr. 01, 2016
Business Acquisition [Line Items]
Gain (Loss) on Disposition of Business	$ 8,100,000	$ 3,100,000
Number of Businesses Acquired	3
Business Acquisition, Transaction Costs	$ 2,100,000	1,600,000
Goodwill, Impairment Loss	$ 0
Maximum
Business Acquisition [Line Items]
Revenue of Business Acquiree Since Acquisition Date Percentage of Total Revenue	1.00%
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Cash Payments to Acquire Businesses	$ 98,700,000
General and Administrative Expense [Member]
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	$ 2,100,000	$ 1,600,000