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Income Taxes (Unrecorded Deferred Income Taxes On Undistributed Earnings Of Foreign Subsidiaries) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Income Tax Disclosure [Abstract] |  |  |
Tax benefit adjustments related to tax cuts and jobs act | $ 1,508 | $ 1,508 |
Additional tax expense from foreign tax positions, related to tax and jobs act | 3,298 | 3,298 |
Tax Act, cumulative foreign earnings | 65,113 | 65,113 |
Foreign earnings repatriated |  |  | $ 30,200
Accrued foreign withholding taxes, unremitted earnings of foreign subsidiaries | 1,220 | 1,220 | $ 7,932
Undistributed earnings from foreign subsidiaries | $ 2,318 | $ 2,318 |

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