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FAIR VALUE - Carrying Amounts and Estimated Fair Values of Other Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets:
Cash and due from financial institutions	$ 30,602	$ 29,467
Interest-earning deposits in other financial institutions	126,397	79,071
Securities available for sale	626,195	554,611
Securities held to maturity	2,482	2,501
Accrued interest receivable	5,035	5,035
Recurring
Financial assets:
Securities available for sale	626,195	554,611
Derivative Asset	10,597	14,345
Financial liabilities:
Derivative Liabilities	10,931	14,702
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and due from financial institutions	30,602	29,467
Interest-earning deposits in other financial institutions	126,397	79,071
Equity investments	2,718	2,542
Securities available for sale	611	0
Securities held to maturity	0	0
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	0	0
Accrued interest receivable	12	0
Derivative Asset	0	0
Financial liabilities:
Demand, savings, and insured money market accounts	1,911,629	1,752,043
Time deposits	0	0
Accrued interest payable	13	11
Derivative Liabilities	0	0
Recurring | Significant Other Observable Inputs (Level 2)
Financial assets:
Cash and due from financial institutions	0	0
Interest-earning deposits in other financial institutions	0	0
Equity investments	0	0
Securities available for sale	625,584	554,611
Securities held to maturity	2,166	2,175
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	0	0
Accrued interest receivable	1,618	1,356
Derivative Asset	10,597	14,345
Financial liabilities:
Demand, savings, and insured money market accounts	0	0
Time deposits	301,203	288,398
Accrued interest payable	277	251
Derivative Liabilities	10,931	14,702
Recurring | Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and due from financial institutions	0	0
Interest-earning deposits in other financial institutions	0	0
Equity investments	0	0
Securities available for sale	0	0
Securities held to maturity	316	326
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	1,556,847	1,514,318
Accrued interest receivable	4,921	4,915
Derivative Asset	0	0
Financial liabilities:
Demand, savings, and insured money market accounts	0	0
Time deposits	0	0
Accrued interest payable	0	0
Derivative Liabilities	0	0
Recurring | Carrying Amount
Financial assets:
Cash and due from financial institutions	30,602	29,467
Interest-earning deposits in other financial institutions	126,397	79,071
Equity investments	2,718	2,542
Securities available for sale	626,195	554,611
Securities held to maturity	2,453	2,469
FHLBNY and FRBNY stock	3,164	3,150
Loans, net and loans held for sale	1,560,335	1,515,709
Accrued interest receivable	6,551	6,271
Derivative Asset	10,597	14,345
Financial liabilities:
Demand, savings, and insured money market accounts	1,911,629	1,752,043
Time deposits	298,752	285,731
Accrued interest payable	290	262
Derivative Liabilities	10,931	14,702
Recurring | Estimated Fair Value
Financial assets:
Cash and due from financial institutions	30,602	29,467
Interest-earning deposits in other financial institutions	126,397	79,071
Equity investments	2,718	2,542
Securities available for sale	626,195	554,611
Securities held to maturity	2,482	2,501
Loans, net and loans held for sale	1,556,847	1,514,318
Accrued interest receivable	6,551	6,271
Derivative Asset	10,597	14,345
Financial liabilities:
Demand, savings, and insured money market accounts	1,911,629	1,752,043
Time deposits	301,203	288,398
Accrued interest payable	290	262
Derivative Liabilities	$ 10,931	$ 14,702

X

- Definition

The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice. Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs). Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank and Federal Home Loan Bank (FHLB) stock represents an equity interest in in a FHLB. They do not have a readily determinable fair values because ownership is restricted and it lacks a market (liquidity).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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