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Income Taxes (Schedule of the Reconciliation of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Income Tax Disclosure [Abstract] |  |  |
Balance at January 1 | $ 1,623 | $ 1,194 | $ 1,117
Changes in unrecognized tax benefits as a result of tax positions taken during a prior year | (15) | 407 | 10
Changes in unrecognized tax benefits as a result of tax position taken during the current year | 263 | 311 | 277
Decreases in unrecognized tax benefits relating to settlements with taxing authorities |  |  |
Reductions to unrecognized tax benefits as a result of a lapse of the applicable statute of limitations | (239) | (289) | (210)
Balance at December 31 | $ 1,632 | $ 1,623 | $ 1,194

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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