The number of derivative instruments held terminated.

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The value of a terminated derivative instrument.

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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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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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

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The number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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

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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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Nominal or face amount used to calculate payment on derivative.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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DERIVATIVES AND HEDGING ACTIVITIES, Classification on Consolidated Statements of Financial Condition (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) DerivativeInstrument	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) DerivativeInstrument
Cash Flow Hedges
Maximum period for future cash flows of forecasted transactions	24 months
Fair value assets	$ 7,100
Designated as Hedging Instrument
Cash Flow Hedges
Number of derivatives terminated \| DerivativeInstrument	34
Derivative notional amount	$ 785,000
Termination value of derivative	16,500
Not Designated as Hedging Instrument
Cash Flow Hedges
Loan level derivative income	1,792	$ 1,163
Posted collateral	10,800
Interest Rate Products \| Designated as Hedging Instrument
Cash Flow Hedges
Estimated reclassification decrease to interest expense during next twelve months	$ 117
Interest Rate Swaps Related to FHLBNY Advances \| Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	4
Count, liabilities \| DerivativeInstrument			32
Notional amount, assets	$ 150,000
Notional amount, liabilities			$ 655,000
Fair value assets	$ 3,944
Fair value liabilities			$ (18,442)
Loan Level Interest Rate Swaps with Borrower \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	109		65
Count, liabilities \| DerivativeInstrument	72
Notional amount, assets	$ 689,408		$ 570,277
Notional amount, liabilities	543,095
Fair value assets	28,104		$ 24,764
Fair value liabilities	$ (16,468)
Loan Level Interest Rate Floors with Borrower \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	46
Count, liabilities \| DerivativeInstrument			41
Notional amount, assets	$ 406,923
Notional amount, liabilities			$ 364,643
Fair value assets	0
Fair value liabilities	$ (5,294)		$ (5,832)
Loan Level Interest Rate Swaps with Third-part Counterparties \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	109
Count, liabilities \| DerivativeInstrument	72		65
Notional amount, assets	$ 689,408
Notional amount, liabilities	543,095		$ 570,277
Fair value assets	16,468
Fair value liabilities	$ (28,104)		$ (24,764)
Loan Level Interest Rate Floors with Third-part Counterparties \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	46		41
Notional amount, assets	$ 406,923		$ 364,643
Fair value assets	5,294		$ 5,832
Fair value liabilities	$ 0