BORROWINGS (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total Long-Term Borrowings	$ 145,320	$ 187,355
Subordinated Debt	49,696	49,601
Secured Debt	32,773	74,906
Junior Subordinated Debentures [Member] \| Capital Trust V Preferred Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	51,510	51,507
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	5,258	5,258
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	$ 6,083	$ 6,083

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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