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Investment Securities Available-For-Sale (Details 2) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | $ 1,876,031 | $ 1,173,268 |
Gross Unrealized Gains | 9,618 | 24,660 |
Gross Unrealized Losses | (22,608) | (461) |
Investment securities available-for-sale | 1,863,041 | 1,197,467 |
Fair Value |  |  |
Less than 12 Months | 1,284,132 | 210,861 |
12 Months or Longer | 124,298 | 3,473 |
Total fair value | 1,408,430 | 214,334 |
Unrealized Losses |  |  |
Less than 12 Months | (19,022) | (451) |
12 Months or Longer | (3,586) | (10) |
Total unrealized losses | (22,608) | (461) |
Gross realized gains and losses |  |  |
Gross realized gains | 221 | 285 | $ 0
Gross realized losses | (901) | (6) | 0
Net realized (losses) gains | (680) | 279 | $ 0
Investment securities pledged as collateral | $ 351,130 | 338,680 |
Number of available-for-sale debt securities | 706 |  |
Number of available-for-sale debt securities in an unrealized loss position | 282 |  |
U.S. Treasury and Federal agencies securities |  |  |
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | $ 1,093,780 | 610,195 |
Gross Unrealized Gains | 3,244 | 9,521 |
Gross Unrealized Losses | (13,018) | (234) |
Investment securities available-for-sale | 1,084,006 | 619,482 |
Fair Value |  |  |
Less than 12 Months | 789,536 | 136,534 |
12 Months or Longer | 84,191 | 0 |
Total fair value | 873,727 | 136,534 |
Unrealized Losses |  |  |
Less than 12 Months | (10,728) | (234) |
12 Months or Longer | (2,290) | 0 |
Total unrealized losses | (13,018) | (234) |
U.S. States and political subdivisions securities |  |  |
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | 95,700 | 78,812 |
Gross Unrealized Gains | 1,130 | 2,346 |
Gross Unrealized Losses | (1,129) | (31) |
Investment securities available-for-sale | 95,701 | 81,127 |
Fair Value |  |  |
Less than 12 Months | 39,585 | 6,391 |
12 Months or Longer | 4,875 | 199 |
Total fair value | 44,460 | 6,590 |
Unrealized Losses |  |  |
Less than 12 Months | (980) | (30) |
12 Months or Longer | (149) | (1) |
Total unrealized losses | (1,129) | (31) |
Mortgage-backed securities - Federal agencies |  |  |
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | 663,441 | 442,748 |
Gross Unrealized Gains | 4,745 | 11,237 |
Gross Unrealized Losses | (8,459) | (196) |
Investment securities available-for-sale | 659,727 | 453,789 |
Fair Value |  |  |
Less than 12 Months | 454,413 | 67,736 |
12 Months or Longer | 35,232 | 3,274 |
Total fair value | 489,645 | 71,010 |
Unrealized Losses |  |  |
Less than 12 Months | (7,312) | (187) |
12 Months or Longer | (1,147) | (9) |
Total unrealized losses | (8,459) | (196) |
Corporate debt securities |  |  |
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | 22,510 | 40,813 |
Gross Unrealized Gains | 499 | 1,556 |
Gross Unrealized Losses | 0 | 0 |
Investment securities available-for-sale | 23,009 | 42,369 |
Fair Value |  |  |
Less than 12 Months | 0 | 0 |
12 Months or Longer | 0 | 0 |
Total fair value | 0 | 0 |
Unrealized Losses |  |  |
Less than 12 Months | 0 | 0 |
12 Months or Longer | 0 | 0 |
Total unrealized losses | 0 | 0 |
Foreign government and other securities |  |  |
Schedule Of Available For Sale Debt Securities [Line Items] |  |  |
Total debt securities available-for-sale | 600 | 700 |
Gross Unrealized Gains | 0 | 0 |
Gross Unrealized Losses | (2) | 0 |
Investment securities available-for-sale | 598 | 700 |
Fair Value |  |  |
Less than 12 Months | 598 | 200 |
12 Months or Longer | 0 | 0 |
Total fair value | 598 | 200 |
Unrealized Losses |  |  |
Less than 12 Months | (2) | 0 |
12 Months or Longer | 0 | 0 |
Total unrealized losses | $ (2) | $ 0 |

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