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v3.19.1

Investment Securities (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) Position | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Investments [Line Items] |  |  |
Gross investment losses | $ 0 | $ 148,000 |
Investment Securities: |  |  |
Consolidated investment securities portfolio modified, years | 41 months 21 days |  | 44 months 3 days
Proceeds from sales of investment securities — available for sale | $ 0 | $ 4,479,000 |
Book value of securities available for sale and held to maturity | $ 118,370,000 |  | $ 115,536,000
Available for sale Securities And Held To Maturity Securities In Unrealized Loss Positions | Position | 129 |  |
Standard & Poor's, AAA Rating [Member] |  |  |
Investments [Line Items] |  |  |
Portfolio rated | 58.50% |  | 57.50%
Securities Rated Below A [Member] |  |  |
Investments [Line Items] |  |  |
Portfolio rated | 8.40% |  | 10.00%
Maximum [Member] |  |  |
Investment Securities: |  |  |
Consolidated investment securities portfolio modified, years | 60 months |  |
Minimum [Member] |  |  |
Investment Securities: |  |  |
Consolidated investment securities portfolio modified, years | 24 months |  |

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- Definition The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details
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