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SECURITIES AND OTHER INVESTMENTS (Schedule of Gross Unrealized Losses and Fair Value of Investments) (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
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Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | $ 169,346 | $ 205,602
Less than 12 Months, Unrealized Losses | (1,466) | (3,700)
More than 12 Months, Fair Value | 1,818,230 | 1,862,395
More than 12 Months, Unrealized Losses | (342,329) | (382,167)
Total, Fair Value | 1,987,576 | 2,067,997
Unrealized Losses, Total | (343,795) | (385,867)
US Government Agencies Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 0 | 0
Less than 12 Months, Unrealized Losses | 0 | 0
More than 12 Months, Fair Value | 1,439 | 1,980
More than 12 Months, Unrealized Losses | (26) | (34)
Total, Fair Value | 1,439 | 1,980
Unrealized Losses, Total | (26) | (34)
US States and Political Subdivisions Debt Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 1,277 | 11,758
Less than 12 Months, Unrealized Losses | (213) | (2,090)
More than 12 Months, Fair Value | 462,306 | 455,931
More than 12 Months, Unrealized Losses | (111,628) | (109,361)
Total, Fair Value | 463,583 | 467,689
Unrealized Losses, Total | (111,841) | (111,451)
Corporate Bond Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 14,899 | 89,450
Less than 12 Months, Unrealized Losses | (167) | (531)
More than 12 Months, Fair Value | 188,773 | 144,155
More than 12 Months, Unrealized Losses | (12,350) | (19,243)
Total, Fair Value | 203,672 | 233,605
Unrealized Losses, Total | (12,517) | (19,774)
Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 42,757 | 35,665
Less than 12 Months, Unrealized Losses | (702) | (547)
More than 12 Months, Fair Value | 188,392 | 208,435
More than 12 Months, Unrealized Losses | (38,655) | (42,599)
Total, Fair Value | 231,149 | 244,100
Unrealized Losses, Total | (39,357) | (43,146)
Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 110,413 | 68,729
Less than 12 Months, Unrealized Losses | (384) | (532)
More than 12 Months, Fair Value | 977,320 | 1,051,894
More than 12 Months, Unrealized Losses | (179,670) | (210,930)
Total, Fair Value | 1,087,733 | 1,120,623
Unrealized Losses, Total | (180,054) | (211,462)
Agency Securities [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 25,224 | 35,665
Less than 12 Months, Unrealized Losses | (86) | (547)
More than 12 Months, Fair Value | 148,257 | 143,657
More than 12 Months, Unrealized Losses | (37,635) | (40,634)
Total, Fair Value | 173,481 | 179,322
Unrealized Losses, Total | (37,721) | (41,181)
Agency Securities [Member] | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 94,214 | 59,707
Less than 12 Months, Unrealized Losses | (288) | (491)
More than 12 Months, Fair Value | 947,499 | 1,011,809
More than 12 Months, Unrealized Losses | (175,899) | (205,144)
Total, Fair Value | 1,041,713 | 1,071,516
Unrealized Losses, Total | (176,187) | (205,635)
Non-agency | Commercial Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 17,533 | 0
Less than 12 Months, Unrealized Losses | (616) | 0
More than 12 Months, Fair Value | 40,135 | 64,778
More than 12 Months, Unrealized Losses | (1,020) | (1,965)
Total, Fair Value | 57,668 | 64,778
Unrealized Losses, Total | (1,636) | (1,965)
Non-agency | Residential Mortgage-Backed Securities [Member] |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Less than 12 months, Fair Value | 16,199 | 9,022
Less than 12 Months, Unrealized Losses | (96) | (41)
More than 12 Months, Fair Value | 29,821 | 40,085
More than 12 Months, Unrealized Losses | (3,771) | (5,786)
Total, Fair Value | 46,020 | 49,107
Unrealized Losses, Total | $ (3,867) | $ (5,827)

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