Basis of Presentation (Narrative) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Accounting Standards Update 2016-09 [Member]
Tax benefits for stock option exercises and restricted stock vesting	$ 13
Accounting Standards Update 2018-02 [Member]
Reclassification amount from accumulated other comprehensive income related to Tax Cuts and jobs Act	$ 471

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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