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DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($) instrument institution	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) instrument institution	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) instrument
Derivative [Line Items]
Interest rate cash flow hedge expense reclassified to interest income (prior year less than)	$ 4,000	$ 2,300	$ 8,000	$ 4,100
Number of variable-rate to fixed-rate swap transactions \| instrument	101		101		123
Derivative, net liability position, aggregate fair value	$ 700		$ 700		$ 4,400
Post Collateral on derivative	$ 1,400		$ 1,400		5,000
Minimum
Derivative [Line Items]
Remaining maturity period	1 year		1 year
Maximum
Derivative [Line Items]
Remaining maturity period	10 years		10 years
Derivatives designated as hedging instruments:
Derivative [Line Items]
Notional	$ 2,450,000		$ 2,450,000		$ 2,200,000
Interest rate options \| Derivatives designated as hedging instruments:
Derivative [Line Items]
Count \| instrument					25
Purchase of derivatives			46,300
Notional	$ 2,300,000		$ 2,300,000		$ 2,200,000
Interest rate options \| Derivatives designated as hedging instruments: \| Balance Sheet Location [Axis]: us-gaap:OtherAssets
Derivative [Line Items]
Count \| instrument	24		24
Notional	$ 2,150,000		$ 2,150,000
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	$ 3,500		$ 3,500		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: \| Balance Sheet Location [Axis]: us-gaap:OtherLiabilities
Derivative [Line Items]
Notional	$ 200,000		$ 200,000
Cash
Derivative [Line Items]
Collateral value against obligations	$ 2,500		$ 2,500