DERIVATIVES AND HEDGING ACTIVITIES - Classification on Consolidated Statements of Financial Condition (Details)	3 Months Ended
Mar. 31, 2023 USD ($) DerivativeInstrument	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) DerivativeInstrument
Cash Flow Hedges
Collateral received against obligations in net asset position			$ 17,800,000
Not Designated as Hedging Instrument
Cash Flow Hedges
Loan level derivative income	$ 3,133,000	$ 6,000
Interest Rate Swaps Related to FHLBNY Advances \| Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	4		4
Notional amount, assets	$ 150,000,000		$ 150,000,000
Fair value assets	$ 14,726,000		$ 17,150,000
Loan Level Interest Rate Swaps with Borrower (Assets) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	14		3
Notional amount, assets	$ 256,325,000		$ 53,311,000
Fair value assets	$ 10,049,000		$ 1,524,000
Loan Level Interest Rate Swaps with Borrower (Liabilities) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	181		185
Notional amount, liabilities	$ 1,161,586,000		$ 1,214,736,000
Fair value liabilities	99,582,000		$ 126,751,000
Posted collateral	$ 0
Loan level interest rate floors with borrower (liabilities) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	39		40
Notional amount, liabilities	$ 294,537,000		$ 326,309,000
Fair value liabilities	5,937,000		9,060,000
Loan level interest rate swaps with third party counterparties (assets) \| Designated as Hedging Instrument
Cash Flow Hedges
Posted collateral	$ 0		$ 0
Loan level interest rate swaps with third party counterparties (assets) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	14		185
Notional amount, assets	$ 256,325,000		$ 1,214,736,000
Fair value assets			126,751,000
Fair value liabilities	10,049,000
Posted collateral	0		0
Collateral received against obligations in net asset position	$ 104,700,000		$ 135,300,000
Loan level interest rate swaps with third party counterparties (liabilities) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	181		3
Notional amount, assets	$ 1,161,586,000
Notional amount, liabilities			$ 53,311,000
Fair value assets	$ 99,582,000
Fair value liabilities			$ 1,524,000
Loan level interest rate floors with third party counterparties (assets) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	39		40
Notional amount, assets	$ 294,537,000		$ 326,309,000
Fair value assets	$ 5,937,000		$ 9,060,000

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Nominal or face amount used to calculate payments on the derivative asset.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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