Amount of unrealized gain (loss) on investments in equity securities classified as available-for-sale securities.

No definition available.

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Available For Sale Equity Securities, Accumulated Gross Unrealized Gain (Loss), Tax

No definition available.

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Basis Of Presentation [Line Items]

No definition available.

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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

No definition available.

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Reclassification of Unrealized Gains on Available for Sale Equity Securities

No definition available.

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Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect

No definition available.

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Basis of Presentation (Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Basis of Presentation (Narrative) (Details) - USD ($)	Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Basis Of Presentation [Line Items]
Unrealized loss on equity investments	$ 33,000	$ 160,000
Accounting Standards Update 2016-01 [Member]
Basis Of Presentation [Line Items]
Reclassification of unrealized gains on AFS equity securities			$ 126,000
Unrealized gain on equity securities			175,000
Unrealized gain on equity securities, tax			49,000
Accounting Standards Update 2018-02 [Member]
Basis Of Presentation [Line Items]
Reclassification due to the adoption of ASU No. 2018-02			$ 557,000