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

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DERIVATIVES AND HEDGING ACTIVITIES - Classification on Consolidated Statements of Financial Condition (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) DerivativeInstrument	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) DerivativeInstrument	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) DerivativeInstrument
Not Designated as Hedging Instrument
Cash Flow Hedges
Loan level derivative income	$ 445	$ 1,544	$ 2,796	$ 5,201
Interest rate swaps related to FHLBNY advances \| Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	4		4
Count, liabilities \| DerivativeInstrument					32
Notional amount, assets	$ 150,000		$ 150,000
Notional amount, liabilities					$ 655,000
Fair value assets	$ 2,811		$ 2,811
Fair value liabilities					$ 18,442
Loan Level Interest Rate Swaps with Borrower (Assets) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	128		128		65
Notional amount, assets	$ 818,370		$ 818,370		$ 570,277
Fair value assets	$ 36,095		$ 36,095		$ 24,764
Loan Level Interest Rate Swaps with Borrower (Liabilities) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	61		61
Notional amount, liabilities	$ 439,198		$ 439,198
Fair value liabilities	(7,414)		(7,414)
Posted collateral	$ 0		$ 0
Loan level interest rate floors with borrower \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	47		47		41
Notional amount, liabilities	$ 405,685		$ 405,685		$ 364,643
Fair value liabilities	(4,072)		(4,072)		$ (5,832)
Loan level interest rate swaps with third-party counterparties (Liabilities) \| Designated as Hedging Instrument
Cash Flow Hedges
Posted collateral	$ 0		$ 0
Loan level interest rate swaps with third-party counterparties (Liabilities) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, liabilities \| DerivativeInstrument	128		128		65
Notional amount, liabilities	$ 818,370		$ 818,370		$ 570,277
Fair value liabilities	(36,095)		(36,095)		$ (24,764)
Posted collateral	$ 23,500		$ 23,500
Loan level interest rate swaps with third party counterparties (Assets) \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	61		61
Notional amount, assets	$ 439,198		$ 439,198
Fair value assets	$ 7,414		$ 7,414
Loan level interest rate floors with third-party counterparties \| Not Designated as Hedging Instrument
Cash Flow Hedges
Count, assets \| DerivativeInstrument	47		47		41
Notional amount, assets	$ 405,685		$ 405,685		$ 364,643
Fair value assets	$ 4,072		$ 4,072		$ 5,832