FEDERAL HOME LOAN BANK ADVANCES AND OTHER BORROWINGS (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Advances from Federal Home Loan Banks	$ 105,000	$ 105,000
FHLB interest rate	3.20%	3.20%
FHLB advance	$ 15,000
FHLB advance rate	0.39%
Cash flow hedge, term	4 years
Overnight borrowings with FHLB	$ 15,000	$ 128,100
Unused commitments from FHLB	1,700,000
Unused short-term or overnight borrowings from correspondent banks	22,000
Unused short-term or overnight borrowings from FRB	1,000,000
Borrowings from the federal reserve’s PPPLF	$ 183,790
Paycheck protection program liquidity facility interest rate	0.35%
Paycheck protection program liquidity facility term	2 years
Interest Rate Swap [Member]
Debt Instrument [Line Items]
FHLB advance	$ 15,000
Federal Reserve Bank of New York [Member]
Debt Instrument [Line Items]
Overnight borrowings with FHLB	0	0
Residential Mortgage [Member]
Debt Instrument [Line Items]
Mortgages pledged as collateral for advances	344,600	347,500
Multifamily Property [Member]
Debt Instrument [Line Items]
Mortgages pledged as collateral for advances	770,900	773,100
Securities [Member]
Debt Instrument [Line Items]
Mortgages pledged as collateral for advances	$ 311,600	$ 154,300

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Amount of unused borrowing capacity under the short-term or overnight borrowings financing arrangement with correspondent banks.

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Amount of unused borrowing capacity under the short-term or overnight borrowings financing arrangement with Federal Reserve Bank.

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Paycheck protection program liquidity facility.

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Paycheck protection program liquidity facility term.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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The maximum balance outstanding at any month end during the period as of the Balance Sheet date.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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