SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Reclassification out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Other comprehensive income/(loss):
Other comprehensive (loss)/income before tax	$ (36,016)	$ 13,088
Provision (Benefit)
Other comprehensive income/(loss), provision (benefit)	(7,563)	2,749
After Tax
Other comprehensive income/(loss) before reclassifications	(26,190)	13,603
Less reclassification adjustments, provision (benefit)	(2,263)	(3,264)
Other comprehensive (loss)/income net of tax	(28,453)	10,339
Available-for-Sale Securities
Other comprehensive income/(loss):
Unrealized gains /(losses) , before tax	(35,602)	21,766
Other comprehensive (loss)/income before tax	(35,604)	21,762
Provision (Benefit)
Unrealized gains/ (losses), provision (benefit)	(7,476)	4,572
Other comprehensive income/(loss), provision (benefit)	(7,476)	4,571
After Tax
Other comprehensive income/(loss) before reclassifications	(28,126)	17,194
Less reclassification adjustments, provision (benefit)	(2)	(3)
Other comprehensive (loss)/income net of tax	(28,128)	17,191
Available-for-Sale Securities \| Other income
Other comprehensive income/(loss):
Less reclassification adjustments, before tax	(2)	(4)
Provision (Benefit)
Less reclassification adjustments, provision (benefit)	0	(1)
After Tax
Less reclassification adjustments, provision (benefit)	(2)	(3)
Held-to-Maturity Securities
Other comprehensive income/(loss):
Less reclassification adjustments, before tax	(392)	(303)
Other comprehensive (loss)/income before tax	(392)	(303)
Provision (Benefit)
Less reclassification adjustments, provision (benefit)	(83)	(64)
Other comprehensive income/(loss), provision (benefit)	(83)	(64)
After Tax
Other comprehensive income/(loss) before reclassifications	0	0
Less reclassification adjustments, provision (benefit)	(309)	(239)
Other comprehensive (loss)/income net of tax	(309)	(239)
Cash Flow Hedges
Other comprehensive income/(loss):
Unrealized gains /(losses) , before tax	2,451	(4,546)
Less reclassification adjustments, before tax	(2,471)	(3,825)
Other comprehensive (loss)/income before tax	(20)	(8,371)
Provision (Benefit)
Unrealized gains/ (losses), provision (benefit)	515	(955)
Less reclassification adjustments, provision (benefit)	(519)	(803)
Other comprehensive income/(loss), provision (benefit)	(4)	(1,758)
After Tax
Other comprehensive income/(loss) before reclassifications	1,936	(3,591)
Less reclassification adjustments, provision (benefit)	(1,952)	(3,022)
Other comprehensive (loss)/income net of tax	$ (16)	$ (6,613)

Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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