Loans (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract	Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale	$ 2,718	$ 1,050
Loans, related parties	6,600	3,500
Loans, related parties, new borrowings	5,700
Loans, related parties, repayments and other reductions	2,600
Past due greater than 90 days and still accruing interest	0	0
Past Due Loans	6,522	5,893
Interest income recognized on nonaccrual loans	0
Estimated interest income	$ 481	$ 234	$ 432
Number of Contracts \| contract	1	4
Pre-Modification Outstanding Recorded Investment	$ 3,081	$ 1,076
Days past due when loans are generally placed on nonaccrual status, in days	90 days	90 days
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due Loans	$ 1,964	$ 1,326
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due Loans	$ 100	$ 1,337
Number of Contracts \| contract	1	3
Pre-Modification Outstanding Recorded Investment	$ 3,081	$ 526
Greater than 90 Days [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due Loans	11	9
Greater than 90 Days [Member] \| Consumer Overdrafts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due Loans	$ 11	$ 9

Days Past Due When Loans Are Generally Placed On Nonaccrual Status, In Days

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Interest Income, Nonaccrual Loans

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Number of financing receivables that have been modified by troubled debt restructurings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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