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DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026 USD ($) instrument institution	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) instrument institution	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) instrument
Derivative [Line Items]
Interest rate cash flow hedge expense reclassified to interest income (prior year less than)	$ 3,800	$ 3,100	$ 11,800	$ 7,200
Number of variable-rate to fixed-rate swap transactions \| instrument	95		95		123
Derivative, net liability position, aggregate fair value	$ 0		$ 0		$ 4,400
Post Collateral on derivative					5,000
Minimum
Derivative [Line Items]
Remaining maturity period	1 year		1 year
Maximum
Derivative [Line Items]
Remaining maturity period	9 years		9 years
Derivatives designated as hedging instruments:
Derivative [Line Items]
Notional	$ 2,400,000		$ 2,400,000		$ 2,200,000
Interest rate options \| Derivatives designated as hedging instruments:
Derivative [Line Items]
Count \| instrument					25
Notional					$ 2,200,000
Interest rate options \| Derivatives designated as hedging instruments: \| Balance Sheet Location [Axis]: us-gaap:OtherAssets
Derivative [Line Items]
Count \| instrument	23		23
Notional	$ 2,100,000		$ 2,100,000
Interest rate options \| Derivatives designated as hedging instruments: \| Balance Sheet Location [Axis]: us-gaap:OtherLiabilities
Derivative [Line Items]
Count \| instrument	3		3
Notional	$ 300,000		$ 300,000
Swap Guarantee
Derivative [Line Items]
Notional					1
Number of financial institutions \| institution	1		1
Aggregate fair value of swaps to customers	$ 3,200		$ 3,200		4,100
Interest rate swap
Derivative [Line Items]
Notional	$ 400,000		$ 400,000		$ 500,000
Number of variable-rate to fixed-rate swap transactions \| instrument	0		0		1
Interest rate swap \| Derivatives designated as hedging instruments:
Derivative [Line Items]
Count \| instrument					2
Interest rate swap \| Derivatives designated as hedging instruments: \| Balance Sheet Location [Axis]: us-gaap:OtherLiabilities
Derivative [Line Items]
Notional	$ 200,000		$ 200,000
Cash
Derivative [Line Items]
Collateral value against obligations	1,100		1,100
Interest Rate Floor \| Derivatives designated as hedging instruments:
Derivative [Line Items]
Count \| instrument					24
Purchase of derivatives			47,600
Notional	$ 2,200,000		$ 2,200,000