Business Acquisitions (Future Amortization Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Acquired Intangible Assets, Amortization Expense, Fiscal Year Maturity [Abstract]
For the year ending December 31, 2016	$ 7,853
For the year ending December 31, 2017	7,368
For the year ending December 31, 2018	6,601
For the year ending December 31, 2019	6,458
For the year ending December 31, 2020	5,893
Thereafter	17,675
Estimated future amortization expense	51,848	$ 49,371
Amortization expense, acquired intangible assets	$ 7,200	$ 7,400	$ 7,300