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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2026	Jun. 30, 2026	Mar. 31, 2026	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2026	Sep. 30, 2025
Other comprehensive (loss)/income:
Other comprehensive (loss)/income before tax	$ (63,332)			$ 15,486			$ (103,352)	$ 8,502
Provision (Benefit)
Other comprehensive income/(loss), provision (benefit)	(13,300)			3,252			(21,704)	1,786
After Tax
Other comprehensive income/(loss) before reclassifications	(50,076)			15,221			(78,161)	15,703
Less reclassification adjustments, provision (benefit)	44			(2,987)			(3,487)	(8,987)
Other comprehensive (loss)/income net of tax	(50,032)	$ (3,163)	$ (28,453)	12,234	$ (15,857)	$ 10,339	(81,648)	6,716
Available-for-Sale Securities
Other comprehensive (loss)/income:
Unrealized gains /(losses) , before tax	(68,180)			18,876			(109,478)	25,797
Other comprehensive (loss)/income before tax	(68,182)			18,874			(109,484)	25,789
Provision (Benefit)
Unrealized gains/ (losses), provision (benefit)	(14,318)			3,964			(22,989)	5,418
Other comprehensive income/(loss), provision (benefit)	(14,318)			3,964			(22,990)	5,417
After Tax
Other comprehensive income/(loss) before reclassifications	(53,862)			14,912			(86,489)	20,379
Less reclassification adjustments, provision (benefit)	(2)			(2)			(5)	(7)
Other comprehensive (loss)/income net of tax	(53,864)			14,910			(86,494)	20,372
Available-for-Sale Securities \| Income Statement Location [Axis]: us-gaap:NoninterestIncomeOtherOperatingIncome
Other comprehensive (loss)/income:
Less reclassification adjustments, before tax	(2)			(2)			(6)	(8)
Provision (Benefit)
Less reclassification adjustments, provision (benefit)	0			0			(1)	(1)
After Tax
Less reclassification adjustments, provision (benefit)	(2)			(2)			(5)	(7)
Held-to-Maturity Securities
Other comprehensive (loss)/income:
Less reclassification adjustments, before tax	58			(186)			521	(204)
Other comprehensive (loss)/income before tax	58			(186)			521	(204)
Provision (Benefit)
Less reclassification adjustments, provision (benefit)	12			(39)			108	(43)
Other comprehensive income/(loss), provision (benefit)	12			(39)			108	(43)
After Tax
Other comprehensive income/(loss) before reclassifications	0			0			0	0
Less reclassification adjustments, provision (benefit)	46			(147)			413	(161)
Other comprehensive (loss)/income net of tax	46			(147)			413	(161)
Cash Flow Hedges
Other comprehensive (loss)/income:
Unrealized gains /(losses) , before tax	4,792			391			10,541	(5,920)
Less reclassification adjustments, before tax	0			(3,593)			(4,930)	(11,163)
Other comprehensive (loss)/income before tax	4,792			(3,202)			5,611	(17,083)
Provision (Benefit)
Unrealized gains/ (losses), provision (benefit)	1,006			82			2,213	(1,244)
Less reclassification adjustments, provision (benefit)	0			(755)			(1,035)	(2,344)
Other comprehensive income/(loss), provision (benefit)	1,006			(673)			1,178	(3,588)
After Tax
Other comprehensive income/(loss) before reclassifications	3,786			309			8,328	(4,676)
Less reclassification adjustments, provision (benefit)	0			(2,838)			(3,895)	(8,819)
Other comprehensive (loss)/income net of tax	$ 3,786			$ (2,529)			$ 4,433	$ (13,495)