Commitments And Contingencies (Reconciliation Of Contingent Consideration Liability) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Business Combination, Contingent Consideration, Reconciliation of Change in Liability [Roll Forward]
Balance at beginning of period	$ 12,545	$ 9,241
Acquisitions	0	7,288
Payments	(4,870)	(2,569)
Accretion	536	716
Fair value adjustments	(1,081)	1,137
Net foreign currency translation adjustment	(135)	353
Balance at end of the period	6,995	16,166
Less current portion in accrued expenses and other current liabilities	(47)	(6,263)
Total long-term portion in other long-term liabilities	6,948	$ 9,903
Contingent consideration, total remaining estimated payments	$ 8,900