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Investment Securities - Other Than Temporarily Impaired Debt Securities (Details) $ in Thousands | Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($) security
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Number of investment securities in unrealized loss positions | security | 10 | 40
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value |  | $ 14,203
Held-to-maturity, Less than 12 continuous months, Unrealized loss |  | (60)
Held-to-maturity, Greater than 12 continuous months, Fair value |  | 7,798
Held-to-maturity, Greater than 12 continuous months, Unrealized loss |  | (89)
Held-to-maturity, Total securities in a loss position, Fair value |  | 22,001
Held-to-maturity, Total securities in a loss position, Unrealized loss | $ 0 | (149)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value | 9,918 | 81,958
Available-for-sale, Less than 12 continuous months, Unrealized loss | (25) | (328)
Available-for-sale, Greater than 12 continuous months, Fair value | 1,790 | 10,552
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (55) | (83)
Available-for-sale, Unrealized loss position, Fair value | 11,708 | 92,510
Available-for-sale, Total securities in a loss position, Unrealized loss | $ (80) | (411)
Available-for-sale and Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] [Abstract] |  |
Total temporarily impaired securities, Less than 12 continuous months, Fair value |  | 96,161
Total temporarily impaired securities, Less than 12 continuous months, Unrealized loss |  | (388)
Total temporarily impaired securities, Greater than 12 continuous months, Fair value |  | 18,350
Total temporarily impaired securities, Greater than 12 continuous months, Unrealized loss |  | (172)
Total temporarily impaired securities, Total securities in a loss position, Fair value |  | 114,511
Total temporarily impaired securities, Total securities in a loss position, Unrealized loss |  | (560)
Number of securities in continuous loss position for more than 12 months | security | 5 |
Number of securities in continuous loss position for less than 12 months | security | 5 |
MBS pass-through securities issued by FHLMC and FNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value |  | 14,203
Held-to-maturity, Less than 12 continuous months, Unrealized loss |  | (60)
Held-to-maturity, Greater than 12 continuous months, Fair value |  | 6,073
Held-to-maturity, Greater than 12 continuous months, Unrealized loss |  | (84)
Held-to-maturity, Total securities in a loss position, Fair value |  | 20,276
Held-to-maturity, Total securities in a loss position, Unrealized loss | $ 0 | (144)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value |  | 4,367
Available-for-sale, Less than 12 continuous months, Unrealized loss |  | (34)
Available-for-sale, Greater than 12 continuous months, Fair value |  | 4,464
Available-for-sale, Greater than 12 continuous months, Unrealized loss |  | (14)
Available-for-sale, Unrealized loss position, Fair value |  | 8,831
Available-for-sale, Total securities in a loss position, Unrealized loss |  | (48)
SBA-backed securities |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Total securities in a loss position, Unrealized loss | 0 | 0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value | 0 | 9,227
Available-for-sale, Less than 12 continuous months, Unrealized loss | 0 | (14)
Available-for-sale, Greater than 12 continuous months, Fair value | 1,790 | 2,448
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (55) | (62)
Available-for-sale, Unrealized loss position, Fair value | 1,790 | 11,675
Available-for-sale, Total securities in a loss position, Unrealized loss | (55) | (76)
CMOs issued by FHLMC |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value |  | 0
Held-to-maturity, Less than 12 continuous months, Unrealized loss |  | 0
Held-to-maturity, Greater than 12 continuous months, Fair value |  | 1,725
Held-to-maturity, Greater than 12 continuous months, Unrealized loss |  | (5)
Held-to-maturity, Total securities in a loss position, Fair value |  | 1,725
Held-to-maturity, Total securities in a loss position, Unrealized loss | 0 | (5)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value | 5,975 | 14,918
Available-for-sale, Less than 12 continuous months, Unrealized loss | (1) | (58)
Available-for-sale, Greater than 12 continuous months, Fair value | 0 | 2,981
Available-for-sale, Greater than 12 continuous months, Unrealized loss | 0 | (6)
Available-for-sale, Unrealized loss position, Fair value | 5,975 | 17,899
Available-for-sale, Total securities in a loss position, Unrealized loss | (1) | (64)
CMOs issued by GNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Total securities in a loss position, Unrealized loss |  | 0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value |  | 7,139
Available-for-sale, Less than 12 continuous months, Unrealized loss |  | (6)
Available-for-sale, Greater than 12 continuous months, Fair value |  | 0
Available-for-sale, Greater than 12 continuous months, Unrealized loss |  | 0
Available-for-sale, Unrealized loss position, Fair value |  | 7,139
Available-for-sale, Total securities in a loss position, Unrealized loss |  | (6)
Debentures of government-sponsored agencies |  |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value | 3,943 | 25,228
Available-for-sale, Less than 12 continuous months, Unrealized loss | (24) | (70)
Available-for-sale, Greater than 12 continuous months, Fair value | 0 | 0
Available-for-sale, Greater than 12 continuous months, Unrealized loss | 0 | 0
Available-for-sale, Unrealized loss position, Fair value | 3,943 | 25,228
Available-for-sale, Total securities in a loss position, Unrealized loss | (24) | (70)
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Total securities in a loss position, Unrealized loss |  | 0
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value |  | 20,579
Available-for-sale, Less than 12 continuous months, Unrealized loss |  | (145)
Available-for-sale, Greater than 12 continuous months, Fair value |  | 659
Available-for-sale, Greater than 12 continuous months, Unrealized loss |  | (1)
Available-for-sale, Unrealized loss position, Fair value |  | 21,238
Available-for-sale, Total securities in a loss position, Unrealized loss |  | (146)
Corporate bonds |  |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] (Deprecated 2019-01-31) |  |
Available-for-sale, Less than 12 continuous months, Fair value |  | 500
Available-for-sale, Less than 12 continuous months, Unrealized loss |  | (1)
Available-for-sale, Greater than 12 continuous months, Fair value |  | 0
Available-for-sale, Greater than 12 continuous months, Unrealized loss |  | 0
Available-for-sale, Unrealized loss position, Fair value |  | 500
Available-for-sale, Total securities in a loss position, Unrealized loss |  | $ (1)

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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