Restructuring Charges (Schedule Of Accrued Restructuring Balances) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 3,956
Restructuring charges	8,737
Cash Payment	(5,779)
Non-Cash Activity	(2,115)
Foreign Exchange Adjustments	0
Ending Balance	4,799
2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	5,477
Cash Payment	(1,434)
Non-Cash Activity	(170)
Foreign Exchange Adjustments	0
Ending Balance	3,873
2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3,956
Restructuring charges	3,260
Cash Payment	(4,345)
Non-Cash Activity	(1,945)
Foreign Exchange Adjustments	0
Ending Balance	926
Severance [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	5,119
Cash Payment	(1,391)
Non-Cash Activity	(25)
Foreign Exchange Adjustments	0
Ending Balance	3,703
Severance [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3,956
Restructuring charges	(1,183)
Cash Payment	(2,470)
Non-Cash Activity	(72)
Foreign Exchange Adjustments	0
Ending Balance	231
Leased facilities and equipment [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	148
Cash Payment	(3)
Non-Cash Activity	(145)
Foreign Exchange Adjustments	0
Ending Balance	0
Leased facilities and equipment [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	3,070
Cash Payment	(1,491)
Non-Cash Activity	(1,144)
Foreign Exchange Adjustments	0
Ending Balance	435
Other Exit Costs [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	210
Cash Payment	(40)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	170
Other Exit Costs [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	1,373
Cash Payment	(384)
Non-Cash Activity	(729)
Foreign Exchange Adjustments	0
Ending Balance	$ 260

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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