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Commitments and Contingencies - Narrative (Details) | 12 Months Ended
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Dec. 31, 2018 USD ($) loan | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Abstract] |  |  |
Rental expense under leases for equipment and premises | $ 2,900,000 | $ 2,900,000 | $ 2,800,000
Rental income under leases | $ 692,000 | 532,000 | $ 424,000
Limit on stop-loss insurance | 1 year |  |
Stop-loss insurance limit per covered individual per year | $ 175,000 |  |
Loans repurchased in 2 year interval | loan | 1 |  |
Total unfunded commitments | $ 308,800,000 | 335,100,000 |
Reserve for unfunded loan commitments and letters of credit | $ 130,000 | $ 152,000 |

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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Definition The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707 + Details
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