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SECURITIES AND OTHER INVESTMENTS (Schedule of Gross Unrealized Losses and Fair Value of Investments) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | $ 646,437 | $ 183,814
Less than 12 Months, Unrealized Losses | (3,520) | (2,542)
More than 12 Months, Fair Value | 1,655,068 | 1,696,552
More than 12 Months, Unrealized Losses | (380,880) | (403,433)
Total, Fair Value | 2,301,505 | 1,880,366
Unrealized Losses, Total | (384,400) | (405,975)
US Government Agencies Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 61,143 | 1,935
Less than 12 Months, Unrealized Losses | (27) | (2)
More than 12 Months, Fair Value | 969 | 1,286
More than 12 Months, Unrealized Losses | (12) | (25)
Total, Fair Value | 62,112 | 3,221
Unrealized Losses, Total | (39) | (27)
US States and Political Subdivisions Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 9,218 | 6,560
Less than 12 Months, Unrealized Losses | (355) | (322)
More than 12 Months, Fair Value | 434,111 | 444,056
More than 12 Months, Unrealized Losses | (137,580) | (129,381)
Total, Fair Value | 443,329 | 450,616
Unrealized Losses, Total | (137,935) | (129,703)
Corporate Bond Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 59,527 | 8,620
Less than 12 Months, Unrealized Losses | (173) | (27)
More than 12 Months, Fair Value | 127,781 | 145,655
More than 12 Months, Unrealized Losses | (7,601) | (9,292)
Total, Fair Value | 187,308 | 154,275
Unrealized Losses, Total | (7,774) | (9,319)
Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 87,575 | 56,155
Less than 12 Months, Unrealized Losses | (378) | (1,547)
More than 12 Months, Fair Value | 188,159 | 181,990
More than 12 Months, Unrealized Losses | (43,701) | (45,241)
Total, Fair Value | 275,734 | 238,145
Unrealized Losses, Total | (44,079) | (46,788)
Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 428,974 | 110,544
Less than 12 Months, Unrealized Losses | (2,587) | (644)
More than 12 Months, Fair Value | 904,048 | 923,565
More than 12 Months, Unrealized Losses | (191,986) | (219,494)
Total, Fair Value | 1,333,022 | 1,034,109
Unrealized Losses, Total | (194,573) | (220,138)
Agency Securities [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 52,923 | 31,291
Less than 12 Months, Unrealized Losses | (185) | (359)
More than 12 Months, Fair Value | 159,546 | 160,880
More than 12 Months, Unrealized Losses | (41,723) | (44,319)
Total, Fair Value | 212,469 | 192,171
Unrealized Losses, Total | (41,908) | (44,678)
Agency Securities [Member] | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 407,085 | 104,477
Less than 12 Months, Unrealized Losses | (2,143) | (546)
More than 12 Months, Fair Value | 881,959 | 895,714
More than 12 Months, Unrealized Losses | (189,564) | (216,208)
Total, Fair Value | 1,289,044 | 1,000,191
Unrealized Losses, Total | (191,707) | (216,754)
Non-agency | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 34,652 | 24,864
Less than 12 Months, Unrealized Losses | (193) | (1,188)
More than 12 Months, Fair Value | 28,613 | 21,110
More than 12 Months, Unrealized Losses | (1,978) | (922)
Total, Fair Value | 63,265 | 45,974
Unrealized Losses, Total | (2,171) | (2,110)
Non-agency | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 21,889 | 6,067
Less than 12 Months, Unrealized Losses | (444) | (98)
More than 12 Months, Fair Value | 22,089 | 27,851
More than 12 Months, Unrealized Losses | (2,422) | (3,286)
Total, Fair Value | 43,978 | 33,918
Unrealized Losses, Total | $ (2,866) | $ (3,384)

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