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

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DERIVATIVES AND HEDGING ACTIVITIES - Classification on Consolidated Statements of Financial Condition (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) DerivativeInstrument	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) DerivativeInstrument	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) DerivativeInstrument
Cash Flow Hedges
Fair value liabilities	$ 0		$ 0
Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Loan level derivative income	$ 559,000	$ 2,494,000	$ 2,351,000	$ 3,657,000
Interest Rate Swaps Related to FHLBNY Advances [Member] \| Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	4		4
Count, liabilities \| DerivativeInstrument					32
Notional amount, assets	$ 150,000,000		$ 150,000,000
Notional amount, liabilities					$ 655,000,000
Fair value assets	$ 2,547,000		$ 2,547,000
Fair value liabilities					$ (18,442,000)
Loan Level Interest Rate Swaps with Borrower \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	137		137		65
Count, liabilities \| DerivativeInstrument	49		49
Notional amount, assets	$ 937,092,000		$ 937,092,000		$ 570,277,000
Notional amount, liabilities	314,786,000		314,786,000
Fair value assets	42,753,000		42,753,000		$ 24,764,000
Fair value liabilities	$ (4,750,000)		$ (4,750,000)
Loan Level Interest Rate Floors with Borrower [Member] \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	47		47
Count, liabilities \| DerivativeInstrument					41
Notional amount, assets	$ 407,249,000		$ 407,249,000
Notional amount, liabilities					$ 364,643,000
Fair value assets	0		0
Fair value liabilities	(4,743,000)		(4,743,000)		$ (5,832,000)
Loan Level Interest Rate Swaps with Third-part Counterparties [Member] \| Designated as Hedging Instrument
Cash Flow Hedges
Posted collateral	$ 0		$ 0
Loan Level Interest Rate Swaps with Third-part Counterparties [Member] \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	137		137
Count, liabilities \| DerivativeInstrument	49		49		65
Notional amount, assets	$ 937,092,000		$ 937,092,000
Notional amount, liabilities	314,786,000		314,786,000		$ 570,277,000
Fair value assets	4,750,000		4,750,000
Fair value liabilities	(42,753,000)		(42,753,000)		$ (24,764,000)
Posted collateral	$ 30,200,000		$ 30,200,000
Loan Level Interest Rate Floors with Third-part Counterparties [Member] \| Not Designated as Hedging Instrument [Member]
Cash Flow Hedges
Count, assets \| DerivativeInstrument	47		47		41
Notional amount, assets	$ 407,249,000		$ 407,249,000		$ 364,643,000
Fair value assets	4,743,000		4,743,000		$ 5,832,000
Fair value liabilities	$ 0		$ 0