Allowance for Loan Losses - Risk Ratings by Segment (Details) (USD $) | Sep. 30, 2014 | Dec. 31, 2013 | Sep. 30, 2013 |
In Thousands, unless otherwise specified |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | $389,263 | $380,731 | $371,646 |
Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 243,936 | 245,943 | 248,889 |
Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 26,954 | 20,382 | 19,409 |
Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 97,651 | 95,289 | 85,130 |
Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 20,722 | 19,117 | 18,218 |
Strong 1 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 314 | 281 | 286 |
Strong 1 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 14 | 16 | 18 |
Strong 1 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Strong 1 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 300 | 265 | 268 |
Strong 1 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Above Average 2 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 39,115 | 38,318 | 38,544 |
Above Average 2 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 11,646 | 14,565 | 14,964 |
Above Average 2 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 1,189 | 804 | 667 |
Above Average 2 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 7,246 | 6,719 | 6,789 |
Above Average 2 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 19,034 | 16,230 | 16,124 |
Satisfactory 3 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 75,458 | 63,823 | 57,377 |
Satisfactory 3 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 50,554 | 45,213 | 36,696 |
Satisfactory 3 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 1,042 | 871 | 2,219 |
Satisfactory 3 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 22,174 | 14,852 | 16,368 |
Satisfactory 3 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 1,688 | 2,887 | 2,094 |
Average 4 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 167,933 | 161,073 | 154,340 |
Average 4 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 108,835 | 100,343 | 110,665 |
Average 4 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 19,445 | 14,938 | 12,640 |
Average 4 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 39,653 | 45,792 | 31,035 |
Average 4 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Watch 5 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 52,083 | 42,791 | 41,971 |
Watch 5 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 32,963 | 32,326 | 30,568 |
Watch 5 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 1,946 | 26 | 21 |
Watch 5 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 17,174 | 10,439 | 11,382 |
Watch 5 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
OAEM 6 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 18,344 | 32,288 | 31,509 |
OAEM 6 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 13,578 | 26,102 | 25,314 |
OAEM 6 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 2,555 | 2,948 | 3,001 |
OAEM 6 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 2,211 | 3,238 | 3,194 |
OAEM 6 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Substandard 7 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 35,497 | 41,532 | 47,228 |
Substandard 7 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 25,827 | 27,115 | 30,273 |
Substandard 7 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 777 | 795 | 861 |
Substandard 7 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 8,893 | 13,622 | 16,094 |
Substandard 7 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Doubtful 8 [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 519 | 625 | 391 |
Doubtful 8 [Member] | Commercial Real Estate Portfolio Segment [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 519 | 263 | 391 |
Doubtful 8 [Member] | Commercial Construction [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 0 | 0 |
Doubtful 8 [Member] | Commercial Other [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | 0 | 362 | 0 |
Doubtful 8 [Member] | Municipal [Member] | ' | ' | ' |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ' | ' | ' |
Commercial and municipal risk-rated loans receivable | $0 | $0 | $0 |