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DERIVATIVES AND HEDGING ACTIVITIES - Classification on Consolidated Statements of Financial Condition (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) DerivativeInstrument	Dec. 31, 2021 USD ($) DerivativeInstrument	Dec. 31, 2020 USD ($)
Cash Flow Hedges
Collateral received against obligations in net asset position	$ 17,800,000	$ 4,600,000
Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Loan level derivative income	$ 3,637,000	$ 2,909,000	$ 8,872,000
Interest Rate Swaps Related to FHLBNY Advances [Member] \| Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	4	4
Notional amount, assets	$ 150,000,000	$ 150,000,000
Fair value assets	$ 17,150,000	$ 4,358,000
Loan Level Interest Rate Swaps with Borrower (Assets) \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	3	98
Notional amount, assets	$ 53,311,000	$ 599,003,000
Fair value assets	$ 1,524,000	$ 27,440,000
Loan Level Interest Rate Swaps with Borrower (Liabilities) \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	185
Notional amount, liabilities	$ 1,214,736,000
Fair value liabilities	126,751,000
Posted collateral	$ 0
Loan Level Interest Rate Swaps with Borrower 3 \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument		87
Notional amount, liabilities		$ 612,610,000
Fair value liabilities		$ (12,620,000)
Loan Level Interest Rate Floors with Borrower \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	40	12
Notional amount, liabilities	$ 326,309,000	$ 100,774,000
Fair value liabilities	9,060,000	$ (53,000)
Loan Level Interest Rate Floors with Borrower 2 \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument		33
Notional amount, assets		$ 291,990,000
Fair value assets		$ 615,000
Loan Level Interest Rate Swaps with Third-part Counterparties 2 \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument		98
Notional amount, liabilities		$ 599,003,000
Fair value liabilities		$ (27,440,000)
Loan Level Interest Rate Swaps with Third-part Counterparties \| Designated as Hedging Instrument
Cash Flow Hedges
Posted collateral	$ 0
Loan Level Interest Rate Swaps with Third-part Counterparties \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument		87
Count, liabilities \| DerivativeInstrument	3
Notional amount, assets		$ 612,610,000
Notional amount, liabilities	$ 53,311,000
Fair value assets		$ 12,620,000
Fair value liabilities	1,524,000
Posted collateral	$ 0
Loan level interest rate swaps with third party counterparties (Assets) \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	185
Notional amount, assets	$ 1,214,736,000
Fair value assets	$ 126,751,000
Loan Level Interest Rate Floors with Third-part Counterparties \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	40	33
Notional amount, assets	$ 326,309,000
Notional amount, liabilities		$ 291,990,000
Fair value assets	9,060,000
Fair value liabilities		(615,000)
Posted collateral		$ 14,000,000.0
Loan Level Interest Rate Floors with Third-part Counterparties 2 \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument		12
Notional amount, assets		$ 100,774,000
Fair value assets		$ 53,000
Posted collateral	$ 135,300,000