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Securities, Available for Sale (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | $ 1,694,806 | $ 1,318,711 |
Unrealized gains | 14,497 | 32,166 |
Unrealized losses | 21,942 | 2,179 |
Estimated fair value | 1,687,361 | 1,348,698 |
Allowance for credit losses on AFS securities | 0 | 0 |
Components of net realized gains (losses) on sale of AFS securities [Abstract] |  |  |
Gross realized gains | 0 | 3 | $ 73
Gross realized (losses) | 0 | 0 | (152)
Net AFS realized gains (losses) | 0 | 3 | (79)
Gains from calls on securities available for sale | 0 | 3 | $ 25
U.S. Treasury [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 73,016 |  |
Unrealized gains | 59 |  |
Unrealized losses | 6 |  |
Estimated fair value | 73,069 |  |
Federal Agency [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 248,454 | 245,590 |
Unrealized gains | 0 | 59 |
Unrealized losses | 8,523 | 2,052 |
Estimated fair value | 239,931 | 243,597 |
State & Municipal [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 95,531 | 42,550 |
Unrealized gains | 116 | 630 |
Unrealized losses | 1,559 | 0 |
Estimated fair value | 94,088 | 43,180 |
Mortgage-Backed, Government Sponsored Enterprises [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 538,036 | 521,448 |
Unrealized gains | 8,036 | 17,079 |
Unrealized losses | 5,589 | 22 |
Estimated fair value | 540,483 | 538,505 |
Mortgage-backed Securities, U.S. Government Agency Securities [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 65,339 | 55,049 |
Unrealized gains | 1,108 | 2,332 |
Unrealized losses | 255 | 47 |
Estimated fair value | 66,192 | 57,334 |
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 484,550 | 311,710 |
Unrealized gains | 2,723 | 7,549 |
Unrealized losses | 5,113 | 58 |
Estimated fair value | 482,160 | 319,201 |
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 139,380 | 114,864 |
Unrealized gains | 939 | 3,739 |
Unrealized losses | 884 | 0 |
Estimated fair value | 139,435 | 118,603 |
Corporate [Member] |  |  |
Debt securities, available-for-sale [Abstract] |  |  |
Amortized cost | 50,500 | 27,500 |
Unrealized gains | 1,516 | 778 |
Unrealized losses | 13 | 0 |
Estimated fair value | $ 52,003 | $ 28,278 |

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