Acquisitions (Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($)
Business Acquisition [Line Items]
Reduction in contingent consideration	$ 1,000
Challenger And Hybrid [Member]
Business Acquisition [Line Items]
Acquisition purchase price	22,807
Acquisition purchase price based on future performance	6,000
Reduction in contingent consideration	1,000
Challenger And Hybrid [Member] | Other Long-Term Liabilities [Member]
Business Acquisition [Line Items]
Acquisition purchase price based on future performance	3,500
Challenger And Hybrid [Member] | Accrued Expenses And Other Current Liabilities [Member]
Business Acquisition [Line Items]
Acquisition purchase price based on future performance	$ 1,500