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		6 Months Ended
	Jun. 30, 2020 USD ($) DerivativeInstrument	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) DerivativeInstrument	Jun. 30, 2019 USD ($)	Mar. 31, 2020 USD ($) DerivativeInstrument	Dec. 31, 2019 USD ($) DerivativeInstrument
Fair Value of Derivative Financial Instruments [Abstract]
Maximum period for future cash flows of forecasted transactions			24 months
Fair value assets	$ 18,475		$ 18,475
Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Number of derivatives terminated \| DerivativeInstrument					2
Derivative notional amount					$ 30,000
Termination value of derivative					$ 175
Posted collateral	6,773		6,773
Not Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Loan level derivative income	2,494	$ 291	3,657	$ 291
Posted collateral	18,847		18,847
Interest Rate Products [Member] \| Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Estimated reclassification decrease to interest expense during next twelve months	$ 9,571		$ 9,571
Interest Rate Swaps Related to FHLBNY Advances [Member] \| Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Count, assets \| DerivativeInstrument						7
Count, liabilities \| DerivativeInstrument	38		38			19
Notional amount, assets						$ 130,000
Notional amount, liabilities	$ 750,000		$ 750,000			315,000
Fair value assets						1,081
Fair value liabilities	$ 30,504		$ 30,504			$ 7,718
Loan Level Interest Rate Swaps with Borrower [Member] \| Not Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Count, assets \| DerivativeInstrument	30		30			7
Count, liabilities \| DerivativeInstrument						1
Notional amount, assets	$ 277,792		$ 277,792			$ 61,038
Notional amount, liabilities						7,205
Fair value assets	20,019		20,019			1,347
Fair value liabilities	$ 0		$ 0			$ 15
Loan Level Interest Rate Floors with Borrower [Member] \| Not Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Count, assets \| DerivativeInstrument	7		7
Notional amount, assets	$ 94,492		$ 94,492
Fair value assets	0		0
Fair value liabilities	$ 1,544		$ 1,544
Loan Level Interest Rate Swaps with Third-part Counterparties [Member] \| Not Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Count, assets \| DerivativeInstrument	30		30			1
Count, liabilities \| DerivativeInstrument						7
Notional amount, assets	$ 277,792		$ 277,792			$ 7,205
Notional amount, liabilities						61,038
Fair value assets	0		0			15
Fair value liabilities	$ 20,019		$ 20,019			$ 1,347
Loan Level Interest Rate Floors with Third-part Counterparties [Member] \| Not Designated as Hedging Instrument [Member]
Fair Value of Derivative Financial Instruments [Abstract]
Count, assets \| DerivativeInstrument	7		7
Notional amount, assets	$ 94,492		$ 94,492
Fair value assets	1,544		1,544
Fair value liabilities	$ 0		$ 0