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Loans (Narrative) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) contract | Dec. 31, 2015 USD ($) loan contract | Dec. 31, 2014 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for sale | $ 1,050 | $ 1,430 |
Loans, related parties | 3,500 | 3,500 |
Loans, related parties, new borrowings | 1,700 |  |
Loans, related parties, repayments and other reductions | 1,700 |  |
Past due greater than 90 days and still accruing interest | 0 | 0 |
Past Due Loans | 5,893 | 4,878 |
Estimated interest income | $ 234 | $ 432 | $ 527
Number of Contracts | contract | 4 | 3 |
Pre-Modification Outstanding Recorded Investment | $ 1,076 | $ 2,024 |
Number of TDR loans in default | loan |  | 2 |
TDRs in default, amount |  | $ 1,300 |
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 | $ 1,326 | $ 1,118 |
Commercial Business [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Past Due Loans | $ 1,337 | $ 933 |
Number of Contracts | contract | 3 | 2 |
Pre-Modification Outstanding Recorded Investment | $ 526 | $ 1,342 |
Greater than 90 Days [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Past Due Loans | 9 | 8 |
Greater than 90 Days [Member] | Consumer Overdrafts [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Past Due Loans | $ 9 | $ 8 |

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 + Details
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