Securities (Narrative) (Details)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018 USD ($) security	Sep. 30, 2018 USD ($) security	Dec. 31, 2017 USD ($) security
Securities in unrealized loss position	95	95	94
Equity securities \| $	$ 1,162,000	$ 1,162,000
Unrealized gain (loss) on equity securities \| $	(4,000)	42,000	$ 197,000
Equity Securities [Member]
Securities in unrealized loss position			2
Equity securities \| $	$ 1,162,000	$ 1,162,000	$ 1,119,000
Debt securities [Member]
Securities in unrealized loss position			92
Obligations of U.S. Government Agencies and Corporations [Member]
Securities in unrealized loss position	20	20	20
Securities in unrealized loss positions for 12 months or more	20	20
Percentage of securities depreciated from their amortized cost basis	1.00%	1.00%
Obligations of State and Political Subdivisions [Member]
Securities in unrealized loss position	29	29	29
Securities in unrealized loss positions for 12 months or more	8	8
Percentage of securities depreciated from their amortized cost basis	1.00%	1.00%
U.S. Government Sponsored Agencies [Member]
Investment portfolio percentage	24.00%	24.00%
Carrying value of pledged assets \| $	$ 57,618,000	$ 57,618,000	$ 47,825,000
Mortgage-Backed Securities [Member]
Investment portfolio percentage	62.00%	62.00%
Securities in unrealized loss position	46	46	43
Securities in unrealized loss positions for 12 months or more	37	37
Percentage of securities depreciated from their amortized cost basis	3.00%	3.00%
Municipal Bonds [Member]
Investment portfolio percentage	14.00%	14.00%
Debt instrument term		5 years

Investment portfolio percentage.

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- Definition

Percentage of securities depreciated from their amortized cost basis

+ References

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- Definition

Securities In Unrealized Loss Positions For Twelve Months Or More

+ References

No definition available.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

For an unclassified balance sheet, this item represents investments in common and preferred stocks and other forms of securities that provide ownership interests in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(b))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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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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