Federal Home Loan Bank Advances Weighted Average Interest Rate inclusive of interest rate Swaps

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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Aggregate amount of interest paid or due on all long-term debt.

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The aggregate interest expense incurred on short-term borrowings including commercial paper and Federal funds purchased and securities sold under agreements to repurchase.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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BORROWINGS (Details Textual) - USD ($)	12 Months Ended
BORROWINGS (Details Textual) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Subordinated Debt	$ 49,696,000	$ 49,601,000
Long-term Debt, Gross	145,661,000
Interest Expense, Long-term Debt	5,400,000	8,200,000	$ 4,200,000
Loans Pledged as Collateral	$ 2,100,000,000	$ 2,500,000,000
Federal Home Loan Bank Advances Weighted Average Interest Rate inclusive of Swaps	1.13%	1.88%
Securities Sold under Agreements to Repurchase	$ 0
Interest expense on short-term borrowings	0	$ 104,000	$ 248,000
Total Long-Term Borrowings	$ 145,320,000	187,355,000
Short-term Debt		50,000,000.0
Long-term Debt [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term Debt		32,773,000
Fixed rate	1.40%
Long-term Debt [Member] \| Long-term Debt [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	1.25%
Parent Company [Member] \| Subordinated Debentures [Member]
Debt Instrument [Line Items]
Subordinated Debt	$ 50,000,000.0	50,000,000.0
Long-term Debt	50,000,000
Capital Trust V Preferred Securities Due in 2037 [Member] \| Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	51,547,000
Total Long-Term Borrowings	$ 51,510,000	$ 51,507,000
Fixed rate	1.70%
Capital Trust V Preferred Securities Due in 2037 [Member] \| Junior Subordinated Debt [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	1.48%
Subordinated Debentures Due in November 2019 [Member] [Domain] \| Subordinated Debentures [Member]
Debt Instrument [Line Items]
Fixed rate		4.75%
Central Bancorp Capital Trust I Securities Due in 2034 [Member] \| Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 5,258,000
Total Long-Term Borrowings	$ 5,258,000	$ 5,258,000
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	2.66%
Central Bancorp Capital Trust I Securities Due in 2034 [Member] \| Junior Subordinated Debt [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	2.44%
Short-term Debt [Member] \| LIBOR [Member] \| Short-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	1.15%
Line of Credit [Member] \| Long-term Debt [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 32,800,000	75,000,000.0
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Federal home loan bank unused remaining available borrowing capacity	1,400,000,000	$ 1,600,000,000
Line of credit maximum borrowing capacity	$ 5,000,000.0