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SECURITIES - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2026 | Dec. 31, 2025
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,977,340 | $ 2,290,766
Gross Unrealized Gains | 5,314 | 10,611
Gross Unrealized Losses | (117,944) | (102,918)
Fair Value | 1,864,710 | 2,198,459
U.S. government and agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 89,315 | 394,361
Gross Unrealized Gains | 546 | 497
Gross Unrealized Losses | (2,216) | (2,383)
Fair Value | 87,645 | 392,475
Municipal securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 217,653 | 218,143
Gross Unrealized Gains | 355 | 627
Gross Unrealized Losses | (24,389) | (22,569)
Fair Value | 193,619 | 196,201
Agency mortgage-backed pass-through securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 839,002 | 831,815
Gross Unrealized Gains | 2,252 | 5,548
Gross Unrealized Losses | (35,367) | (29,377)
Fair Value | 805,887 | 807,986
Agency collateralized mortgage obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 723,509 | 737,627
Gross Unrealized Gains | 1,483 | 3,375
Gross Unrealized Losses | (51,007) | (43,937)
Fair Value | 673,985 | 697,065
Corporate bonds and other |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 107,861 | 108,820
Gross Unrealized Gains | 678 | 564
Gross Unrealized Losses | (4,965) | (4,652)
Fair Value | $ 103,574 | $ 104,732

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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