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Securities - Summary of Amortized Cost and Fair Values of Securities Held-to-maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Schedule Of Held To Maturity Securities [Line Items] |  |
Held-to-maturity Securities, Amortized Cost | $ 4,412 | $ 99,266
Held-to-maturity Securities, Gross Unrealized Gains | 86 | 133
Held-to-maturity Securities, Gross Unrealized Losses |  | (1,660)
Held-to-maturity Securities, Fair Value | 4,498 | 97,739
Obligations of States, Municipalities, and Political Subdivisions |  |
Schedule Of Held To Maturity Securities [Line Items] |  |
Held-to-maturity Securities, Amortized Cost | 4,412 | 23,835
Held-to-maturity Securities, Gross Unrealized Gains | 86 | 40
Held-to-maturity Securities, Gross Unrealized Losses |  | (210)
Held-to-maturity Securities, Fair Value | $ 4,498 | 23,665
Agency, Residential Mortgage-Backed Securities |  |
Schedule Of Held To Maturity Securities [Line Items] |  |
Held-to-maturity Securities, Amortized Cost |  | 40,082
Held-to-maturity Securities, Gross Unrealized Gains |  | 93
Held-to-maturity Securities, Gross Unrealized Losses |  | (531)
Held-to-maturity Securities, Fair Value |  | 39,644
Non-Agency, Residential Mortgage-Backed Securities |  |
Schedule Of Held To Maturity Securities [Line Items] |  |
Held-to-maturity Securities, Amortized Cost |  | 35,349
Held-to-maturity Securities, Gross Unrealized Losses |  | (919)
Held-to-maturity Securities, Fair Value |  | $ 34,430

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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=118954083&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=118939692&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=118939692&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=118939692&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=118939692&loc=d3e27232-111563 + Details
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