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Securities - Amortized Cost and Fair Value of Available-for-sale Securities (Details) - USD ($) | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Debt securities available-for-sale: |  |
Amortized Cost | $ 159,649,000 | $ 153,566,000
Gross Unrealized Gains | 205,000 | 165,000
Gross Unrealized Losses | (3,644,000) | (1,787,000)
Fair Value | 156,209,802 | 151,944,567
U.S. Government-sponsored enterprises (GSEs) [Member] |  |
Debt securities available-for-sale: |  |
Amortized Cost | 30,147,000 | 26,207,000
Gross Unrealized Gains | 0 | 1,000
Gross Unrealized Losses | (844,000) | (432,000)
Fair Value | 29,303,000 | 25,776,000
Municipal securities [Member] |  |
Debt securities available-for-sale: |  |
Amortized Cost | 10,141,000 | 9,122,000
Gross Unrealized Gains | 10,000 | 28,000
Gross Unrealized Losses | (265,000) | (147,000)
Fair Value | 9,886,000 | 9,003,000
Other debt securities [Member] |  |
Debt securities available-for-sale: |  |
Amortized Cost | 975,000 | 974,000
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (51,000) | (24,000)
Fair Value | 924,000 | 950,000
Mortgage-backed securities (GSEs) [Member] |  |
Debt securities available-for-sale: |  |
Amortized Cost | 118,386,000 | 117,263,000
Gross Unrealized Gains | 195,000 | 136,000
Gross Unrealized Losses | (2,484,000) | (1,184,000)
Fair Value | $ 116,097,000 | $ 116,215,000

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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale. + 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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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale. + 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 (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of debt 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 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 Reference 2: 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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