DERIVATIVE FINANCIAL INSTRUMENTS - Schedule of Fair Values of Derivative Instruments (Details) $ in Thousands	Sep. 30, 2025 USD ($) instrument	Dec. 31, 2024 USD ($) instrument
Derivatives in Cash Flow Hedging Relationships
Derivative [Line Items]
Notional	$ 2,000,000	$ 1,500,000
Derivative asset	23,149	14,265
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional	8,664,234	7,802,391
Total derivatives	$ 18,920	$ 9,977
Interest rate options | Derivatives in Cash Flow Hedging Relationships
Derivative [Line Items]
Count | instrument	23	18
Notional	$ 2,000,000	$ 1,500,000
Derivative asset	23,149	14,265
Interest rate options | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative asset	122,255	153,980
Derivative liability	(122,257)	(153,980)
Interest rate options | Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Notional	3,105,482	2,942,675
Interest rate options | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional	3,107,460	2,942,675
Interest rate lock commitments with clients | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative asset	1,064	612
Derivative liability		(18)
Interest rate lock commitments with clients | Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Notional	65,213	41,238
Interest rate lock commitments with clients | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional		3,658
Forward sale commitments | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative asset	66	200
Derivative liability	(139)	(39)
Forward sale commitments | Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Notional	19,216	28,927
Forward sale commitments | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional	42,319	27,071
FX forwards | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative asset	1,269	1,407
Derivative liability	(1,218)	(1,205)
FX forwards | Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Notional	13,665	26,716
FX forwards | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional	13,310	25,924
Risk participation agreements sold | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative liability	(187)	(90)
Risk participation agreements sold | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional	111,041	110,948
Risk participation agreements purchased | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative asset	73	25
Risk participation agreements purchased | Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Notional	133,029	97,201
Financial derivatives related to sales of certain Visa Class B shares | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative liability	(5,155)	(5,180)
Financial derivatives related to sales of certain Visa Class B shares | Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Notional	$ 53,499	$ 55,358