Restructuring Charges (Schedule Of Accrued Restructuring Balances) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 1,335	$ 290
Restructuring charges	8,507	5,197
Cash Payment	(4,931)	(4,012)
Non-Cash Activity	(944)	(116)
Foreign Exchange Adjustments	(11)	(24)
Ending Balance	3,956	1,335	$ 290
2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	8,046
Cash Payment	(3,146)
Non-Cash Activity	(944)
Foreign Exchange Adjustments	0
Ending Balance	3,956	0
2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	1,200	0
Restructuring charges	461	4,588
Cash Payment	(1,661)	(3,388)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	0	0
Ending Balance	0	1,200	0
2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	135	245
Restructuring charges	0	369	2,967
Cash Payment	(124)	(455)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	(11)	(24)
Ending Balance	0	135	245
2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0	45
Restructuring charges		240
Cash Payment		(169)
Non-Cash Activity		(116)
Foreign Exchange Adjustments		0
Ending Balance		0	45
Severance [Member] | 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	6,449
Cash Payment	(2,493)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	3,956	0
Severance [Member] | 2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	282	0
Restructuring charges	0	2,815
Cash Payment	(282)	(2,533)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	0	0
Ending Balance	0	282	0
Severance [Member] | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0	47
Restructuring charges	0	3
Cash Payment	0	(50)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	0	0
Ending Balance	0	0	47
Severance [Member] | 2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0	29
Restructuring charges		(6)
Cash Payment		(23)
Non-Cash Activity		0
Foreign Exchange Adjustments		0
Ending Balance		0	29
Lease Facility Costs [Member] | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0	0
Restructuring charges		96
Cash Payment		(96)
Non-Cash Activity		0
Foreign Exchange Adjustments		0
Ending Balance		0	0
Other Exit Costs [Member] | 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	1,597
Cash Payment	(653)
Non-Cash Activity	(944)
Foreign Exchange Adjustments	0
Ending Balance	0	0
Other Exit Costs [Member] | 2018 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	918	0
Restructuring charges	461	1,773
Cash Payment	(1,379)	(855)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	0	0
Ending Balance	0	918	0
Other Exit Costs [Member] | 2017 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	135	198
Restructuring charges	0	270
Cash Payment	(124)	(309)
Non-Cash Activity	0	0
Foreign Exchange Adjustments	(11)	(24)
Ending Balance	0	135	198
Other Exit Costs [Member] | 2016 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 0	16
Restructuring charges		246
Cash Payment		(146)
Non-Cash Activity		(116)
Foreign Exchange Adjustments		0
Ending Balance		$ 0	$ 16