DERIVATIVE FINANCIAL INSTRUMENTS - Schedule of Effect of Derivative Instruments on the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	$ (58,377)	$ (1,597)	$ (79,415)	$ 14,328
Gain (Loss) Reclassified from AOCI into Income	(1,159)	(3,275)	(4,497)	(7,004)
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	1,514	(839)	2,075	(1,207)
Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	29,418	(3,081)	25,565	(15,763)
Gain (Loss) Recognized in Income on Related Hedged Items	(29,515)	3,040	(25,582)	15,743
Interest rate swaps on borrowings \| Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	(10,497)	1,532	(21,535)	16,596
Gain (Loss) Recognized in Income on Related Hedged Items	10,486	(1,552)	21,519	(16,559)
Interest rate swaps on investment securities \| Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	39,915	(4,613)	47,100	(32,359)
Gain (Loss) Recognized in Income on Related Hedged Items	(40,001)	4,592	(47,101)	32,302
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	(58,378)	(1,596)	(81,621)	14,328
Gain (Loss) Reclassified from AOCI into Income	(2,523)	(4,373)	(8,499)	(10,299)
Interest rate contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	378	(826)	834	(679)
Mortgage contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	1,119	8	1,207	(495)
Foreign currency contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ 17	$ (21)	$ 34	$ (33)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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