DERIVATIVES AND HEDGING ACTIVITIES - Classification on Consolidated Statements of Financial Condition (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) DerivativeInstrument	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) DerivativeInstrument	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) DerivativeInstrument
Cash Flow Hedges
Collateral received against obligations in net asset position	$ 8,900,000		$ 8,900,000		$ 13,500,000
Not Designated as Hedging Instrument
Cash Flow Hedges
Loan level derivative income	132,000	$ 783,000	1,623,000	$ 6,353,000
Interest Rate Products | Designated as Hedging Instrument | Cash Flow Hedging
Cash Flow Hedges
Notional amount, assets	150,000,000		150,000,000		150,000,000
Notional amount, liabilities	350,000,000		350,000,000		200,000,000
Fair value assets	8,061,000		8,061,000		12,492,000
Interest Rate Products | Designated as Hedging Instrument | Fair value hedges
Cash Flow Hedges
Notional amount, liabilities	500,000,000		500,000,000		500,000,000
Interest Rate Products | Not Designated as Hedging Instrument
Cash Flow Hedges
Notional amount, assets	1,672,995,000		1,672,995,000		1,682,961,000
Notional amount, liabilities	1,672,995,000		1,672,995,000		1,682,961,000
Fair value assets	$ 97,575,000		$ 97,575,000		$ 114,671,000
Loan Level Interest Rate Swaps with Borrower (Assets) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets | DerivativeInstrument	57		57		49
Notional amount, assets	$ 622,834,000		$ 622,834,000		$ 491,394,000
Fair value assets	$ 21,325,000		$ 21,325,000		$ 10,985,000
Loan Level Interest Rate Swaps with Borrower (Liabilities) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities | DerivativeInstrument	172		172		178
Notional amount, liabilities	$ 1,050,161,000		$ 1,050,161,000		$ 1,121,085,000
Fair value liabilities	(76,250,000)		(76,250,000)		$ (103,570,000)
Collateral Already Posted, Aggregate Fair Value	0		0
Loan level interest rate floors with borrower (assets) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities | DerivativeInstrument					7
Notional amount, liabilities					$ 40,761,000
Fair value liabilities					$ (116,000)
Loan level interest rate floors with borrower (liabilities) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets | DerivativeInstrument					2
Notional amount, assets					$ 29,721,000
Loan level interest rate swaps with third party counterparties (assets) | Designated as Hedging Instrument
Cash Flow Hedges
Collateral Already Posted, Aggregate Fair Value	$ 0		$ 0		$ 0
Loan level interest rate swaps with third party counterparties (assets) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets | DerivativeInstrument	172		172		178
Notional amount, assets	$ 1,050,161,000		$ 1,050,161,000		$ 1,121,085,000
Fair value assets	76,250,000		76,250,000		103,570,000
Collateral Already Posted, Aggregate Fair Value	3,500,000		3,500,000		0
Collateral received against obligations in net asset position	$ 60,000,000.0		$ 60,000,000.0		$ 94,700,000
Loan level interest rate swaps with third party counterparties (liabilities) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities | DerivativeInstrument	57		57		49
Notional amount, liabilities	$ 622,834,000		$ 622,834,000		$ 491,394,000
Fair value liabilities	$ (21,325,000)		$ (21,325,000)		$ (10,985,000)
Loan level interest rate floors with third party counterparties (assets) | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets | DerivativeInstrument					2
Notional amount, assets					$ 29,721,000
Loan level interest rate floors with third party counterparties | Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets | DerivativeInstrument					7
Notional amount, assets					$ 40,761,000
Fair value assets					$ 116,000