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Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | $ 1,165,310 | $ 547,711
Gross Unrealized Gains | 26,099 | 28,395
Gross Unrealized Losses | (8,048) | (506)
Fair Value | 1,183,361 | 575,600
U.S. Treasury and U.S. government sponsored entities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 89,919 | 11,798
Gross Unrealized Gains | 53 | 101
Gross Unrealized Losses | (1,502) | (54)
Fair Value | 88,470 | 11,845
State and political subdivisions |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 485,125 | 344,160
Gross Unrealized Gains | 22,776 | 22,350
Gross Unrealized Losses | (618) | (204)
Fair Value | 507,283 | 366,306
Mortgage-backed securities - residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 569,235 | 157,106
Gross Unrealized Gains | 2,778 | 4,919
Gross Unrealized Losses | (5,909) | (243)
Fair Value | 566,104 | 161,782
Collateralized mortgage obligations - residential |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 12,956 | 25,654
Gross Unrealized Gains | 290 | 742
Gross Unrealized Losses | (5) | (3)
Fair Value | 13,241 | 26,393
Corporate bonds |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 3,604 | 3,582
Gross Unrealized Gains | 77 | 132
Gross Unrealized Losses | (14) | (2)
Fair Value | 3,667 | 3,712
Small Business Administration |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized Cost | 4,471 | 5,411
Gross Unrealized Gains | 125 | 151
Gross Unrealized Losses | 0 | 0
Fair Value | $ 4,596 | $ 5,562

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