Restructuring Charges (Schedule Of Accrued Restructuring) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 290
Restructuring charges	2,241
Cash Payment	(1,945)
Non-Cash Activity	(96)
Foreign Exchange Adjustments	(23)
Ending Balance	467
2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	1,665
Cash Payment	(1,359)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	306
2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	245
Restructuring charges	369
Cash Payment	(455)
Non-Cash Activity	0
Foreign Exchange Adjustments	(23)
Ending Balance	136
2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	45
Restructuring charges	207
Cash Payment	(131)
Non-Cash Activity	(96)
Foreign Exchange Adjustments	0
Ending Balance	25
Severance [Member] | 2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	974
Cash Payment	(974)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	0
Severance [Member] | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	47
Restructuring charges	3
Cash Payment	(50)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	0
Severance [Member] | 2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	29
Restructuring Reserve Accrual Adjustment	(1)
Cash Payment	(3)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	25
Lease Facility Costs [Member] | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	96
Cash Payment	(96)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	0
Other Exit Costs | 2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	691
Cash Payment	(385)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	306
Other Exit Costs | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	198
Restructuring charges	270
Cash Payment	(309)
Non-Cash Activity	0
Foreign Exchange Adjustments	(23)
Ending Balance	136
Other Exit Costs | 2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	16
Restructuring charges	208
Cash Payment	(128)
Non-Cash Activity	(96)
Foreign Exchange Adjustments	0
Ending Balance	$ 0