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INVESTMENT SECURITIES - Amortized Cost of Investment Securities Held to Maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | $ 2,074,465 | $ 2,184,497
Aaa |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 1,107,845 |
Aa1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 148,923 |
Aa2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 184,341 |
Aa3 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 185,166 |
A1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 65,665 |
A2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 20,317 |
Non-rated |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 362,208 |
U.S. Government-sponsored agency securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 345,531 | 374,002
U.S. Government-sponsored agency securities | Aaa |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 345,531 |
U.S. Government-sponsored agency securities | Aa1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored agency securities | Aa2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored agency securities | Aa3 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored agency securities | A1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored agency securities | A2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored agency securities | Non-rated |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
State and municipal |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 1,085,921 | 1,099,201
State and municipal | Aaa |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 120,801 |
State and municipal | Aa1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 148,923 |
State and municipal | Aa2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 184,341 |
State and municipal | Aa3 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 185,166 |
State and municipal | A1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 65,665 |
State and municipal | A2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 20,317 |
State and municipal | Non-rated |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 360,708 |
U.S. Government-sponsored mortgage-backed securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 641,513 | $ 709,794
U.S. Government-sponsored mortgage-backed securities | Aaa |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 641,513 |
U.S. Government-sponsored mortgage-backed securities | Aa1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored mortgage-backed securities | Aa2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored mortgage-backed securities | Aa3 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored mortgage-backed securities | A1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored mortgage-backed securities | A2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
U.S. Government-sponsored mortgage-backed securities | Non-rated |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 1,500 |
Foreign investment | Aaa |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | Aa1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | Aa2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | Aa3 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | A1 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | A2 |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | 0 |
Foreign investment | Non-rated |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total | $ 1,500 |

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