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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
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Income Tax Contingency [Line Items] |  |
Gross liability for unrecognized tax benefits, exclusive of interest and penalties | $ 14,851 | $ 14,367
Unrecognized tax benefits that would affect effective tax rate | 14,369 | 13,774
Interest and penalties on unrecognized benefits | 1,453 | $ 1,289
Settlement and Lapse of Statute |  |
Income Tax Contingency [Line Items] |  |
Unrecognized tax benefits within the next twelve months | $ 2,964 |

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- Definition The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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