Basis of Presentation (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017
Forfeited, Shares		4,345	90
Accounting Standards Update 2016-09 [Member]
Tax benefits for stock option exercises and restricted stock vesting	$ 29	$ 42
Forfeited, Shares	4,095	4,345
Accounting Standards Update 2018-02 [Member]
Reclassification amount from accumulated other comprehensive income related to Tax Cuts and jobs Act		$ 471

Tax Cuts And Jobs Act Of 2017 Reclassification From Aoci To Retained Earnings Tax Effect

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- Definition

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

+ References

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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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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