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Investment Securities (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Available for sale |  |
Total investment securities available for sale, Amortized Cost | $ 68,181 | $ 65,244
Total investment securities available for sale, Gross Unrealized Gains | 185 | 163
Total investment securities available for sale, Gross Unrealized Losses | 763 | 927
Available-for-sale securities, investment securities, Fair Value | 67,603 | 64,480
US government agencies [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 8,749 | 6,271
Total investment securities available for sale, Gross Unrealized Gains | 1 | 1
Total investment securities available for sale, Gross Unrealized Losses | 97 | 113
Available-for-sale securities, investment securities, Fair Value | 8,653 | 6,159
SBA securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 4,087 | 1,453
Total investment securities available for sale, Gross Unrealized Gains |  |
Total investment securities available for sale, Gross Unrealized Losses | 24 | 16
Available-for-sale securities, investment securities, Fair Value | 4,063 | 1,437
State and political subdivisions [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 11,242 | 20,625
Total investment securities available for sale, Gross Unrealized Gains | 179 | 141
Total investment securities available for sale, Gross Unrealized Losses | 25 | 292
Available-for-sale securities, investment securities, Fair Value | 11,396 | 20,474
Mortgage-backed securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 44,103 | 36,895
Total investment securities available for sale, Gross Unrealized Gains | 5 | 21
Total investment securities available for sale, Gross Unrealized Losses | 617 | 506
Available-for-sale securities, investment securities, Fair Value | 43,491 | 36,410
Mortgage-backed securities [Member] | FHLMC [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 9,102 | 10,922
Total investment securities available for sale, Gross Unrealized Gains |  |
Total investment securities available for sale, Gross Unrealized Losses | 149 | 185
Available-for-sale securities, investment securities, Fair Value | 8,953 | 10,737
Mortgage-backed securities [Member] | FNMA [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 29,383 | 24,827
Total investment securities available for sale, Gross Unrealized Gains | 3 | 19
Total investment securities available for sale, Gross Unrealized Losses | 386 | 277
Available-for-sale securities, investment securities, Fair Value | 29,000 | 24,569
Mortgage-backed securities [Member] | GNMA [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 5,618 | 1,146
Total investment securities available for sale, Gross Unrealized Gains | 2 | 2
Total investment securities available for sale, Gross Unrealized Losses | 82 | 44
Available-for-sale securities, investment securities, Fair Value | $ 5,538 | $ 1,104

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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -Subparagraph (b)-(g) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62557-112803 + Details
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