Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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BORROWINGS (Trust Preferred Securities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Face Amount	$ 71.0	$ 71.0
Junior Subordinated Debentures [Member] \| Capital Trust V Preferred Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Face Amount	$ 50.0
Fixed rate	6.52%
Junior Subordinated Debentures [Member] \| Capital Trust V Preferred Securities Due in 2037 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.48%
Junior Subordinated Debentures [Member] \| Slades Ferry Trust I Preferred Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Face Amount	$ 10.0
Junior Subordinated Debentures [Member] \| Slades Ferry Trust I Preferred Securities Due in 2034 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.79%
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Face Amount	$ 5.1
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust I Securities Due in 2034 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.44%
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Face Amount	$ 5.9
Fixed rate	7.015%
Junior Subordinated Debentures [Member] \| Central Bancorp Capital Trust II Securities Due in 2037 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
Subordinated Debt [Member] \| Subordinated Debentures Due in October 2019 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Subordinated Debt [Member] \| Subordinated Debentures Due in November 2019 [Member] [Domain]
Debt Instrument [Line Items]
Fixed rate	4.75%
Subordinated Debt [Member] \| Subordinated Debentures Due in November 2019 [Member] [Domain] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.98%