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

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).

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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).

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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