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Debt Securities Held-to-Maturity - Mortgage Backed Securities Held-to-Maturity (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 8,648 | $ 8,762
Gross Unrealized Gains | 370 | 129
Gross Unrealized Losses | 0 | 5
Estimated Fair Value | 9,018 | 8,886
Mortgage Backed Securities Pass Through Certificates |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 8,648 | 8,762
Gross Unrealized Gains | 370 | 129
Gross Unrealized Losses | 0 | 5
Estimated Fair Value | $ 9,018 | $ 8,886

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- Definition Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121645371&loc=SL120269820-111563 + Details
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