BORROWINGS (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total Long-Term Borrowings	$ 107,742	$ 107,895
Subordinated Debt	34,635	34,589
Junior Subordinated Debentures [Member] | Capital Trust V Preferred Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	51,500	51,497
Junior Subordinated Debentures [Member] | Slades Ferry Trust I Preferred Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	10,224	10,219
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	5,302	5,516
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Total Long-Term Borrowings	$ 6,081	$ 6,074