Recent Accounting Standards Update (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Recent Accounting Standards Update [Abstract]
Amount transferred from AOCI to retained earnings		$ 588,000
Reclassification from AOCI to retained earnings	$ 156,000	$ 156,000
Federal statutory tax rate		21.00%	34.00%
Unrealized gain (loss) on equity securities	$ (4,000)	$ 42,000	$ 197,000

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax liability and asset pursuant to Tax Cuts and Jobs Act of 2017.

No definition available.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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- References

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- Definition

Amount reclassified to unappropriated retained earnings from accumulated increase (decrease) in the fair value of the financial assets (liabilities) of the collateralized financing entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 65
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96859814&loc=SL52289068-158248

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- Definition

Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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