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Income Taxes (Schedule Of Effective Income Tax Rate For Continuing Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Income Tax Disclosure [Abstract] |  |
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | $ 2,670 | $ (5,647)
Income tax expense at federal statutory rate | 21.00% | 21.00%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount | $ 982 | $ 1,027
State taxes, net of federal income tax benefit | 1.90% | 1.10%
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount | $ 0 | $ (601)
Effective Income Tax Rate Reconciliation Capital Loss Carryforwards Valuation Allowance, Amount | 35 | 40
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount | $ (182) | $ (205)
Changes in estimates related to prior year tax provision | 0.00% | 2.20%
Non-deductible expenses | 1.20% | (0.70%)
Research and development tax credit | (1.40%) | 0.80%
Foreign rate differences | 7.70% | (3.80%)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount | $ 239 | $ (307)
Foreign tax incentives | (11.50%) | 6.20%
Effective Income Tax Rate Reconciliation, Deduction, Dividends, Amount | $ 33 | $ 0
Effective Income Tax Rate Reconciliation, Deduction, Dividend, Percent | (0.30%) | 0.00%
Valuation allowance for capital loss carry-forwards | 0.30% | (0.10%)
Effective Income Tax Rate Reconciliation, Deduction, Amount | $ 3,097 | $ 6,226
Effective income tax rate for income from continuing operations | (24.40%) | (23.20%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount | $ 191 | $ 251
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent | 1.50% | (0.90%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount | $ 155 | $ 190
Effective Income Tax Rate Reconciliation, Tax Credit, Amount | (1,468) | (1,676)
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income | $ 508 | $ 702
Effective Income Tax Rate Reconciliation - U.S. Tax on Foreign Branch Income - Percentage | 4.00% | (2.60%)
Income Taxes [Line Items] |  |
Effective Income Tax Rate Reconciliation, Deduction, Amount | $ 3,097 | $ 6,226
Effective Income Tax Rate Reconciliation, Deduction, Percent | 24.40% | 23.20%

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