Securities (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) security item	Dec. 31, 2016 USD ($)
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	$ 55,312	$ 40,776
Available-for-sale Securities Pledged as Collateral	12,123	11,756
Reportable Legal Entities [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	9,940	24,637
Available-for-sale Securities, Gross Realized Gains	113	487
Available-for-sale Securities, Gross Realized Losses	0	0
US Treasuries [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	1,858	1,833
US Agency Obligations [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	23,850	13,113
Municipals [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	12,274	9,947
Corporates [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Available-for-sale Securities	$ 3,942	$ 3,878
S&P Rated AA [Member] \| Mortgage Backed Securities, Other [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Number Of Securities Held \| security	11
S&P Rated AA [Member] \| US Agency Obligations [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Number Of Securities Held \| item	21
S&P Rated AA [Member] \| Municipals [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Number Of Securities Held \| item	17
S&P Rated AA [Member] \| Corporates [Member]
Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]
Number Of Securities Held \| security	5

Number Of Securities Evaluated For Other Than Temporary Impairment [Line Items]

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Number Of Securities Held

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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The fair value of available-for-sale securities that serve as collateral for borrowings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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