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Loans - Narrative (Detail) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017
--- | --- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |  |
Net deferred loan fees and costs | $ 301 | $ 301 |
Total Loans | 539,821 | 522,201 | $ 514,707
Consumer and other loans |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Total Loans | 17,137 | 17,078 | $ 17,028
Consumer and other loans | Demand deposit overdrafts |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Total Loans | $ 249 | $ 232 |

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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + 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=82891408&loc=d3e4428-111522 + Details
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- Definition Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533 + Details
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