Securities Sold Under Agreements to Repurchase and Other Short-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Securities Sold Under Agreements to Repurchase and Other Short-Term Debt [Abstract]
Borrowing capacity through unsecured borrowing lines	$ 65.00
Loans pledged to the FHLBB	369.78	276.94
Additional short or long-term borrowing capacity with FHLBB	$ 246.92

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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