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SECURITIES AND OTHER INVESTMENTS (Schedule of Gross Unrealized Losses and Fair Value of Investments) (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | $ 673,237 | $ 183,814
Less than 12 Months, Unrealized Losses | (3,801) | (2,542)
More than 12 Months, Fair Value | 1,659,851 | 1,696,552
More than 12 Months, Unrealized Losses | (340,361) | (403,433)
Total, Fair Value | 2,333,088 | 1,880,366
Unrealized Losses, Total | (344,162) | (405,975)
US Government Agencies Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 11,861 | 1,935
Less than 12 Months, Unrealized Losses | (22) | (2)
More than 12 Months, Fair Value | 862 | 1,286
More than 12 Months, Unrealized Losses | (12) | (25)
Total, Fair Value | 12,723 | 3,221
Unrealized Losses, Total | (34) | (27)
US States and Political Subdivisions Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 3,711 | 6,560
Less than 12 Months, Unrealized Losses | (38) | (322)
More than 12 Months, Fair Value | 454,035 | 444,056
More than 12 Months, Unrealized Losses | (117,400) | (129,381)
Total, Fair Value | 457,746 | 450,616
Unrealized Losses, Total | (117,438) | (129,703)
Corporate Bond Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 47,770 | 8,620
Less than 12 Months, Unrealized Losses | (69) | (27)
More than 12 Months, Fair Value | 107,271 | 145,655
More than 12 Months, Unrealized Losses | (5,125) | (9,292)
Total, Fair Value | 155,041 | 154,275
Unrealized Losses, Total | (5,194) | (9,319)
Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 94,586 | 56,155
Less than 12 Months, Unrealized Losses | (511) | (1,547)
More than 12 Months, Fair Value | 183,084 | 181,990
More than 12 Months, Unrealized Losses | (42,418) | (45,241)
Total, Fair Value | 277,670 | 238,145
Unrealized Losses, Total | (42,929) | (46,788)
Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 515,309 | 110,544
Less than 12 Months, Unrealized Losses | (3,161) | (644)
More than 12 Months, Fair Value | 914,599 | 923,565
More than 12 Months, Unrealized Losses | (175,406) | (219,494)
Total, Fair Value | 1,429,908 | 1,034,109
Unrealized Losses, Total | (178,567) | (220,138)
Agency Securities [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 60,304 | 31,291
Less than 12 Months, Unrealized Losses | (232) | (359)
More than 12 Months, Fair Value | 158,881 | 160,880
More than 12 Months, Unrealized Losses | (40,594) | (44,319)
Total, Fair Value | 219,185 | 192,171
Unrealized Losses, Total | (40,826) | (44,678)
Agency Securities [Member] | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 447,134 | 104,477
Less than 12 Months, Unrealized Losses | (2,598) | (546)
More than 12 Months, Fair Value | 887,972 | 895,714
More than 12 Months, Unrealized Losses | (173,115) | (216,208)
Total, Fair Value | 1,335,106 | 1,000,191
Unrealized Losses, Total | (175,713) | (216,754)
Non-agency | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 34,282 | 24,864
Less than 12 Months, Unrealized Losses | (279) | (1,188)
More than 12 Months, Fair Value | 24,203 | 21,110
More than 12 Months, Unrealized Losses | (1,824) | (922)
Total, Fair Value | 58,485 | 45,974
Unrealized Losses, Total | (2,103) | (2,110)
Non-agency | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 68,175 | 6,067
Less than 12 Months, Unrealized Losses | (563) | (98)
More than 12 Months, Fair Value | 26,627 | 27,851
More than 12 Months, Unrealized Losses | (2,291) | (3,286)
Total, Fair Value | 94,802 | 33,918
Unrealized Losses, Total | $ (2,854) | $ (3,384)

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