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STOCKHOLDERS' EQUITY (Change in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | $ 4,832,639 | $ 3,185,216 | $ 3,142,879 | $ 3,043,686 | $ 2,548,928 | $ 2,556,327 | $ 3,142,879 | $ 2,556,327
Net current period other comprehensive (loss) income | 37,678 | 12,929 | 25,971 | 90,280 | (8,289) | (30,949) | 76,578 | 51,042
Ending balance | 4,917,058 | 4,832,639 | 3,185,216 | 3,182,416 | 3,043,686 | 2,548,928 | 4,917,058 | 3,182,416
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] |  |  |  |  |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | (294,373) |  | (317,142) | (330,804) |  | (302,532) | (317,142) | (302,532)
Other comprehensive income (loss) before reclassification | 35,020 |  |  | 66,856 |  |  | 57,721 | 33,438
Amounts reclassified from AOCI into earnings | (3) |  |  | (3) |  |  | 65 | 5,143
Net current period other comprehensive (loss) income | 35,017 |  |  | 66,853 |  |  | 57,786 | 38,581
Ending balance | (259,356) | (294,373) |  | (263,951) | (330,804) |  | (259,356) | (263,951)
Unrealized Gains (Losses) for AFS Securities Transferred to HTM |  |  |  |  |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | 0 |  | 0 | 1 |  | 6 | 0 | 6
Other comprehensive income (loss) before reclassification | 0 |  |  | 0 |  |  | 0 | 0
Amounts reclassified from AOCI into earnings | 0 |  |  | 0 |  |  | 0 | (5)
Net current period other comprehensive (loss) income | 0 |  |  | 0 |  |  | 0 | (5)
Ending balance | 0 | 0 |  | 1 | 1 |  | 0 | 1
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] |  |  |  |  |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | (26,540) |  | (43,078) | (52,775) |  | (42,165) | (43,078) | (42,165)
Other comprehensive income (loss) before reclassification | 2,863 |  |  | 23,589 |  |  | 19,401 | 12,979
Amounts reclassified from AOCI into earnings | 0 |  |  | 0 |  |  | 0 | 0
Net current period other comprehensive (loss) income | 2,863 |  |  | 23,589 |  |  | 19,401 | 12,979
Ending balance | (23,677) | (26,540) |  | (29,186) | (52,775) |  | (23,677) | (29,186)
Unrealized Gains (Losses) on BOLI |  |  |  |  |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | 127 |  | 534 | 991 |  | 1,342 | 534 | 1,342
Other comprehensive income (loss) before reclassification | 0 |  |  | 0 |  |  | (10) | (16)
Amounts reclassified from AOCI into earnings | (202) |  |  | (162) |  |  | (599) | (497)
Net current period other comprehensive (loss) income | (202) |  |  | (162) |  |  | (609) | (513)
Ending balance | (75) | 127 |  | 829 | 991 |  | (75) | 829
AOCI Attributable to Parent [Member] |  |  |  |  |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | (320,786) | (333,715) | (359,686) | (382,587) | (374,298) | (343,349) | (359,686) | (343,349)
Other comprehensive income (loss) before reclassification | 37,883 |  |  | 90,445 |  |  | 77,112 | 46,401
Amounts reclassified from AOCI into earnings | (205) |  |  | (165) |  |  | (534) | 4,641
Net current period other comprehensive (loss) income | 37,678 | 12,929 | 25,971 | 90,280 | (8,289) | (30,949) | 76,578 | 51,042
Ending balance | $ (283,108) | $ (320,786) | $ (333,715) | $ (292,307) | $ (382,587) | $ (374,298) | $ (283,108) | $ (292,307)

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