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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, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Tax Disclosure [Abstract] |  |  |
Balance at January 1 | $ 1,632 | $ 1,623 | $ 1,194
Changes in unrecognized tax benefits as a result of tax positions taken during a prior year | (135) | (15) | 407
Changes in unrecognized tax benefits as a result of tax position taken during the current year | 192 | 263 | 311
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 | (286) | (239) | (289)
Balance at December 31 | $ 1,403 | $ 1,632 | $ 1,623

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=84176650&loc=SL37586934-109318 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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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