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SECURITIES (Schedule of Contractual maturities) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Amortized Cost | $ 1,583,736 | $ 395,453
Available for Sale, Fair Value |  |
Debt Securities, Available-for-sale | 1,571,148 | 412,860
Held to Maturity, Amortized Cost |  |
Debt Securities, Held-to-maturity | 1,066,818 | 724,512
Held to Maturity, Fair Value |  |
Fair Value | 1,064,133 | 752,177
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesWithinOneYearAmortizedCost | 26,414 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesWithinOneYearFairValue | 26,579 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterOneThroughFiveYearsAmortizedCost | 818,467 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterOneThroughFiveYearsFair Value | 809,993 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterFiveThroughTenYearsAmortizedCost | 927,300 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterFiveThroughTenYearsFairValue | 917,542 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterTenYearsAmortizedCost | 878,373 |
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterTenYearsFairValue | 881,167 |
AvailableForSaleandHeldToMaturityDebtSecuritiesAmortizedCost | 2,650,554 |
Debt Securities, Available-for-sale and Held-to-maturity Fair Value | 2,635,281 |
US Government Agencies Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 10,000 |
Due after one year to five years | 43,831 |
Due after five to ten years | 163,562 |
Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 217,393 | 22,476
Available for Sale, Fair Value |  |
Due in one year or less | 10,007 |
Due in one year or less | 44,065 |
Due after five to ten years | 161,410 |
Due after ten years | 0 |
Debt Securities, Available-for-sale | 215,482 | 24,116
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 32,987 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Debt Securities, Held-to-maturity | 32,987 | 0
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 32,546 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Fair Value | 32,546 |
Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 24,411 |
Due after one year to five years | 782,464 |
Due after five to ten years | 536,691 |
Due after ten years | 240,170 |
Available for Sale, Fair Value |  |
Due in one year or less | 24,570 |
Due in one year or less | 774,291 |
Due after five to ten years | 528,685 |
Due after ten years | 243,602 |
Debt Securities, Available-for-sale | 1,571,148 |
Held to Maturity, Amortized Cost |  |
Due in one year or less | 2,003 |
Due after one year to five years | 36,003 |
Due after five to ten years | 390,609 |
Due after ten years | 638,203 |
Held to Maturity, Fair Value |  |
Due in one year or less | 2,009 |
Due after one year to five years | 35,702 |
Due after five to ten years | 388,857 |
Due after ten years | 637,565 |
Fair Value | 1,064,133 |
US Treasury Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 643,068 |
Due after five to ten years | 230,399 |
Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 873,467 | 0
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 633,504 |
Due after five to ten years | 227,944 |
Due after ten years | 0 |
Debt Securities, Available-for-sale | 861,448 | 0
Held to Maturity, Amortized Cost |  |
Due in one year or less | 2,003 |
Due after one year to five years | 0 |
Due after five to ten years | 100,557 |
Due after ten years | 0 |
Debt Securities, Held-to-maturity | 102,560 | 4,017
Held to Maturity, Fair Value |  |
Due in one year or less | 2,009 |
Due after one year to five years | 0 |
Due after five to ten years | 100,233 |
Due after ten years | 0 |
Fair Value | 102,242 | 4,077
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 14,411 |
Due after one year to five years | 95,373 |
Due after five to ten years | 142,730 |
Due after ten years | 112,441 |
Debt Securities, Available-for-sale, Amortized Cost | 364,955 | 224,293
Available for Sale, Fair Value |  |
Due in one year or less | 14,563 |
Due in one year or less | 96,519 |
Due after five to ten years | 139,331 |
Due after ten years | 113,520 |
Debt Securities, Available-for-sale | 363,933 | 233,629
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 3,016 |
Due after five to ten years | 288,552 |
Due after ten years | 201,444 |
Debt Securities, Held-to-maturity | 493,012 | 356,085
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 3,156 |
Due after five to ten years | 287,116 |
Due after ten years | 206,964 |
Fair Value | 497,236 | 374,121
Agency collateralized mortgage obligations [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 78,966 |
Debt Securities, Available-for-sale, Amortized Cost | 78,966 | 88,687
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 79,677 |
Debt Securities, Available-for-sale | 79,677 | 91,683
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 415,736 |
Debt Securities, Held-to-maturity | 415,736 | 335,993
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 408,845 |
Fair Value | 408,845 | 344,119
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 192 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Debt Securities, Available-for-sale, Amortized Cost | 192 | 790
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 203 |
Due after five to ten years | 0 |
Due after ten years | 0 |
Debt Securities, Available-for-sale | 203 | 807
Single issuer trust preferred securities issued by banks [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 489 |
Debt Securities, Available-for-sale, Amortized Cost | 489 | 489
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 491 |
Debt Securities, Available-for-sale | 491 | 488
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 1,500 |
Due after ten years | 0 |
Debt Securities, Held-to-maturity | 1,500 | 1,500
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 1,508 |
Due after ten years | 0 |
Fair Value | 1,508 | 1,498
Pooled Trust Preferred Securities Issued By Banks And Insurers [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 1,199 |
Debt Securities, Available-for-sale, Amortized Cost | 1,199 | 1,429
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 1,000 |
Debt Securities, Available-for-sale | 1,000 | 1,056
Small Business Administration Pooled Securities [Member] |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 47,075 |
Debt Securities, Available-for-sale, Amortized Cost | 47,075 | 57,289
Available for Sale, Fair Value |  |
Due in one year or less | 0 |
Due in one year or less | 0 |
Due after five to ten years | 0 |
Due after ten years | 48,914 |
Debt Securities, Available-for-sale | 48,914 | 61,081
Held to Maturity, Amortized Cost |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 21,023 |
Debt Securities, Held-to-maturity | 21,023 | 26,917
Held to Maturity, Fair Value |  |
Due in one year or less | 0 |
Due after one year to five years | 0 |
Due after five to ten years | 0 |
Due after ten years | 21,756 |
Fair Value | $ 21,756 | $ 28,362

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