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Investment Securities (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016
Available for sale |  |
Total investment securities available for sale, Amortized Cost | $ 78,580 | $ 65,244
Total investment securities available for sale, Gross Unrealized Gains | 358 | 163
Total investment securities available for sale, Gross Unrealized Losses | 498 | 927
Available-for-sale securities, investment securities, Fair Value | 78,440 | 64,480
US government agencies [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 8,754 | 6,271
Total investment securities available for sale, Gross Unrealized Gains | 14 | 1
Total investment securities available for sale, Gross Unrealized Losses | 58 | 113
Available-for-sale securities, investment securities, Fair Value | 8,710 | 6,159
SBA securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 4,357 | 1,453
Total investment securities available for sale, Gross Unrealized Gains |  |
Total investment securities available for sale, Gross Unrealized Losses | 18 | 16
Available-for-sale securities, investment securities, Fair Value | 4,339 | 1,437
State and political subdivisions [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 20,088 | 20,625
Total investment securities available for sale, Gross Unrealized Gains | 329 | 141
Total investment securities available for sale, Gross Unrealized Losses | 60 | 292
Available-for-sale securities, investment securities, Fair Value | 20,357 | 20,474
Mortgage-backed securities [Member] |  |
Available for sale |  |
Total investment securities available for sale, Amortized Cost | 45,381 | 36,895
Total investment securities available for sale, Gross Unrealized Gains | 15 | 21
Total investment securities available for sale, Gross Unrealized Losses | 362 | 506
Available-for-sale securities, investment securities, Fair Value | $ 45,034 | $ 36,410

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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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- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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