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Debt Securities Held-to-Maturity - Mortgage Backed Securities Held-to-Maturity (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 9,448 | $ 9,505
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 128 | 256
Estimated Fair Value | 9,320 | 9,249
Mortgage Backed Securities Pass Through Certificates |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 9,448 | 9,505
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 128 | 256
Estimated Fair Value | $ 9,320 | $ 9,249

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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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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=82897076&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss 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 (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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- Definition Fair value of 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 (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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