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Investment Securities - Other Than Temporarily Impaired Debt Securities (Details) | Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($) 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 | 217 | 10
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value | $ 201,204,000 |
Held-to-maturity, Less than 12 continuous months, Unrealized loss | (2,867,000) |
Held-to-maturity, Greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, Greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total securities in a loss position, Fair value | 201,204,000 |
Held-to-maturity, Total securities in a loss position, Unrealized loss | (2,867,000) | $ 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 797,781,000 | 9,918,000
Available-for-sale, Less than 12 continuous months, Unrealized loss | (12,411,000) | (25,000)
Available-for-sale, Greater than 12 continuous months, Fair value | 14,173,000 | 1,790,000
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (615,000) | (55,000)
Available-for-sale, Unrealized loss position, Fair value | 811,954,000 | 11,708,000
Available-for-sale, Total securities in a loss position, Unrealized loss | (13,026,000) | (80,000)
Available-for-sale and Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] |  |
Total temporarily impaired securities, Less than 12 continuous months, Fair value | 998,985,000 | 9,918,000
Total temporarily impaired securities, Less than 12 continuous months, Unrealized loss | (15,278,000) | (25,000)
Total temporarily impaired securities, Greater than 12 continuous months, Fair value | 14,173,000 | 1,790,000
Total temporarily impaired securities, Greater than 12 continuous months, Unrealized loss | (615,000) | (55,000)
Total temporarily impaired securities, Total securities in a loss position, Fair value | 1,013,158,000 | 11,708,000
Total temporarily impaired securities, Total securities in a loss position, Unrealized loss | $ (15,893,000) | (80,000)
Number of securities in continuous loss position for more than 12 months | security | 9 |
Number of securities in continuous loss position for less than 12 months | security | 208 |
Available-for-sale securities in unrealized loss position, allowance for credit loss | $ 0 |
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 | 76,619,000 |
Held-to-maturity, Less than 12 continuous months, Unrealized loss | (712,000) |
Held-to-maturity, Greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, Greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total securities in a loss position, Fair value | 76,619,000 |
Held-to-maturity, Total securities in a loss position, Unrealized loss | (712,000) | 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 263,474,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (2,784,000) |
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 | 263,474,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (2,784,000) |
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
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 7,478,000 | 0
Available-for-sale, Less than 12 continuous months, Unrealized loss | (112,000) | 0
Available-for-sale, Greater than 12 continuous months, Fair value | 1,209,000 | 1,790,000
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (43,000) | (55,000)
Available-for-sale, Unrealized loss position, Fair value | 8,687,000 | 1,790,000
Available-for-sale, Total securities in a loss position, Unrealized loss | (155,000) | (55,000)
CMOs issued by FHLMC |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value | 54,811,000 |
Held-to-maturity, Less than 12 continuous months, Unrealized loss | (1,045,000) |
Held-to-maturity, Greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, Greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total securities in a loss position, Fair value | 54,811,000 |
Held-to-maturity, Total securities in a loss position, Unrealized loss | (1,045,000) | 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 226,175,000 | 5,975,000
Available-for-sale, Less than 12 continuous months, Unrealized loss | (4,677,000) | (1,000)
Available-for-sale, Greater than 12 continuous months, Fair value | 4,415,000 | 0
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (152,000) | 0
Available-for-sale, Unrealized loss position, Fair value | 230,590,000 | 5,975,000
Available-for-sale, Total securities in a loss position, Unrealized loss | (4,829,000) | (1,000)
CMOs issued by GNMA |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 44,790,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (553,000) |
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 | 44,790,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (553,000) |
CMOs issued by FNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Total securities in a loss position, Unrealized loss | 0 | 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 37,348,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (611,000) |
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 | 37,348,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (611,000) |
Debentures of government-sponsored agencies |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value | 50,571,000 |
Held-to-maturity, Less than 12 continuous months, Unrealized loss | (901,000) |
Held-to-maturity, Greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, Greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total securities in a loss position, Fair value | 50,571,000 |
Held-to-maturity, Total securities in a loss position, Unrealized loss | (901,000) |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 148,979,000 | 3,943,000
Available-for-sale, Less than 12 continuous months, Unrealized loss | (2,527,000) | (24,000)
Available-for-sale, Greater than 12 continuous months, Fair value | 8,549,000 | 0
Available-for-sale, Greater than 12 continuous months, Unrealized loss | (420,000) | 0
Available-for-sale, Unrealized loss position, Fair value | 157,528,000 | 3,943,000
Available-for-sale, Total securities in a loss position, Unrealized loss | (2,947,000) | (24,000)
U.S. Treasury securities |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 11,629,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (256,000) |
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 | 11,629,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (256,000) |
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-maturity, Less than 12 continuous months, Fair value | 19,203,000 |
Held-to-maturity, Less than 12 continuous months, Unrealized loss | (209,000) |
Held-to-maturity, Greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, Greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total securities in a loss position, Fair value | 19,203,000 |
Held-to-maturity, Total securities in a loss position, Unrealized loss | (209,000) | $ 0
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 17,552,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (381,000) |
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 | 17,552,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (381,000) |
Corporate bonds |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 38,495,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (506,000) |
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 | 38,495,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | (506,000) |
Asset-backed securities |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, Less than 12 continuous months, Fair value | 1,861,000 |
Available-for-sale, Less than 12 continuous months, Unrealized loss | (4,000) |
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 | 1,861,000 |
Available-for-sale, Total securities in a loss position, Unrealized loss | $ (4,000) |

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