| **Allowance for Loan Losses (Tables)**                                   | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              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| **Receivables [Abstract]**                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        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| Allowance for loan losses by class of financing receivable and allowance | A breakdown of the allowance for loan losses as of March 31, 2015, December 31, 2014, and March 31, 2014, by class of financing receivable and allowance element, is presented in the following tables:As of March 31, 2015Specific Reserves on Loans Evaluated Individually for Impairment General Reserves on Loans Based on Historical Loss Experience Reserves for Qualitative Factors UnallocatedReserves Total ReservesCommercial            Real estate$248,000 $1,094,000 $1,775,000 $— $3,117,000   Construction396,000 157,000 254,000 — 807,000   Other347,000 521,000 846,000 — 1,714,000Municipal— — 16,000 — 16,000Residential            Term421,000 298,000 389,000 — 1,108,000   Construction— 10,000 13,000 — 23,000Home equity line of credit24,000 716,000 304,000 — 1,044,000Consumer— 318,000 208,000 — 526,000Unallocated— — — 1,841,000 1,841,000 $1,436,000 $3,114,000 $3,805,000 $1,841,000 $10,196,000As of December 31, 2014Specific Reserves on Loans Evaluated Individually for Impairment General Reserves on Loans Based on Historical Loss Experience Reserves for Qualitative Factors UnallocatedReserves Total ReservesCommercial            Real estate$346,000 $1,444,000 $1,742,000 $— $3,532,000   Construction413,000 186,000 224,000 — 823,000   Other129,000 624,000 752,000 — 1,505,000Municipal— — 15,000 — 15,000Residential            Term519,000 297,000 369,000 — 1,185,000   Construction— 9,000 11,000 — 20,000Home equity line of credit396,000 376,000 288,000 — 1,060,000Consumer— 346,000 196,000 — 542,000Unallocated— — — 1,662,000 1,662,000 $1,803,000 $3,282,000 $3,597,000 $1,662,000 $10,344,000As of March 31, 2014Specific Reserves on Loans Evaluated Individually for Impairment General Reserves on Loans Based on Historical Loss Experience Reserves for Qualitative Factors UnallocatedReserves Total ReservesCommercial            Real estate$1,019,000 $1,707,000 $1,774,000 $— $4,500,000   Construction276,000 154,000 160,000 — 590,000   Other834,000 690,000 717,000 — 2,241,000Municipal— — 15,000 — 15,000Residential            Term574,000 303,000 355,000 — 1,232,000   Construction— 10,000 12,000 — 22,000Home equity line of credit83,000 343,000 282,000 — 708,000Consumer— 323,000 194,000 — 517,000Unallocated— — — 1,830,000 1,830,000 $2,786,000 $3,530,000 $3,509,000 $1,830,000 $11,655,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Summary of Risk Ratings for Loans                                        | The following table summarizes the risk ratings for the Company's commercial real estate, commercial construction, commercial other, and municipal loans as of March 31, 2015: CommercialReal Estate CommercialConstruction CommercialOther MunicipalLoans All Risk-Rated Loans1 Strong$11,000 $— $344,000 $— $355,0002 Above Average11,599,000 766,000 8,282,000 24,687,000 45,334,0003 Satisfactory52,828,000 2,227,000 24,758,000 1,590,000 81,403,0004 Average108,480,000 25,867,000 55,120,000 — 189,467,0005 Watch36,816,000 2,567,000 17,642,000 — 57,025,0006 OAEM9,670,000 2,509,000 1,669,000 — 13,848,0007 Substandard22,617,000 747,000 7,640,000 — 31,004,0008 Doubtful— — — — —Total$242,021,000 $34,683,000 $115,455,000 $26,277,000 $418,436,000The following table summarizes the risk ratings for the Company's commercial real estate, commercial construction, commercial other, and municipal loans as of December 31, 2014: CommercialReal Estate CommercialConstruction CommercialOther MunicipalLoans All Risk-Rated Loans1 Strong$12,000 $— $330,000 $— $342,0002 Above Average12,668,000 771,000 7,210,000 18,789,000 39,438,0003 Satisfactory50,275,000 1,983,000 24,232,000 1,635,000 78,125,0004 Average108,719,000 23,345,000 44,895,000 — 176,959,0005 Watch36,974,000 1,567,000 18,171,000 — 56,712,0006 OAEM9,846,000 2,519,000 1,970,000 — 14,335,0007 Substandard23,817,000 747,000 7,723,000 — 32,287,0008 Doubtful— — — — —Total$242,311,000 $30,932,000 $104,531,000 $20,424,000 $398,198,000The following table summarizes the risk ratings for the Company's commercial real estate, commercial construction, commercial other, and municipal loans as of March 31, 2014: CommercialReal Estate CommercialConstruction CommercialOther MunicipalLoans All Risk-Rated Loans1 Strong$15,000 $— $261,000 $— $276,0002 Above Average9,287,000 773,000 7,458,000 15,926,000 33,444,0003 Satisfactory44,918,000 1,080,000 16,864,000 1,864,000 64,726,0004 Average102,361,000 16,388,000 46,447,000 — 165,196,0005 Watch33,079,000 — 10,828,000 — 43,907,0006 OAEM26,951,000 2,668,000 3,883,000 — 33,502,0007 Substandard23,576,000 777,000 11,495,000 — 35,848,0008 Doubtful— — 40,000 — 40,000Total$240,187,000 $21,686,000 $97,276,000 $17,790,000 $376,939,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Allowance for Loan Losses Transactions                                   | The following table presents allowance for loan losses activity by class for the three months ended March 31, 2015, and allowance for loan loss balances by class and related loan balances by class as of March 31, 2015: CommercialMunicipalResidentialHome Equity Line of CreditConsumerUnallocatedTotal Real EstateConstructionOther TermConstruction    For the three months ended March 31, 2015Beginning balance$3,532,000$823,000$1,505,000$15,000$1,185,000$20,000$1,060,000$542,000$1,662,000$10,344,000Charge offs122,000—2,000—83,000—447,00062,000—716,000Recoveries——4,000—6,000—22,00036,000—68,000Provision (credit)(293,000)(16,000)207,0001,000—3,000409,00010,000179,000500,000Ending balance$3,117,000$807,000$1,714,000$16,000$1,108,000$23,000$1,044,000$526,000$1,841,000$10,196,000Allowance for loan losses as of March 31, 2015Ending balance specifically evaluated for impairment$248,000$396,000$347,000$—$421,000$—$24,000$—$—$1,436,000Ending balance collectively evaluated for impairment$2,869,000$411,000$1,367,000$16,000$687,000$23,000$1,020,000$526,000$1,841,000$8,760,000Related loan balances as of March 31, 2015Ending balance$242,021,000$34,683,000$115,455,000$26,277,000$383,869,000$13,036,000$104,100,000$19,728,000$—$939,169,000Ending balance specifically evaluated for impairment$12,705,000$1,380,000$2,721,000$—$16,348,000$—$1,654,000$25,000$—$34,833,000Ending balance collectively evaluated for impairment$229,316,000$33,303,000$112,734,000$26,277,000$367,521,000$13,036,000$102,446,000$19,703,000$—$904,336,000The following table presents allowance for loan losses activity by class for the year-ended December 31, 2014 and allowance for loan loss balances by class and related loan balances by class as of December 31, 2014: CommercialMunicipalResidential Home Equity Line of CreditConsumerUnallocatedTotal Real Estate Construction Other Term Construction     For the year ended December 31, 2014Beginning balance$4,602,000 $575,000 $2,276,000$15,000$1,099,000 $21,000 $675,000$573,000$1,678,000$11,514,000Charge offs1,205,000 — 989,000—699,000 — 153,000449,000—3,495,000Recoveries144,000 — 758,000—36,000 25,000 16,000196,000—1,175,000Provision (credit)(9,000) 248,000 (540,000)—749,000 (26,000) 522,000222,000(16,000)1,150,000Ending balance$3,532,000 $823,000 $1,505,000$15,000$1,185,000 $20,000 $1,060,000$542,000$1,662,000$10,344,000Allowance for loan losses as of December 31, 2014Ending balance specifically evaluated for impairment$346,000 $413,000 $129,000$—$519,000 $— $396,000$—$—$1,803,000Ending balance collectively evaluated for impairment$3,186,000 $410,000 $1,376,000$15,000$666,000 $20,000 $664,000$542,000$1,662,000$8,541,000Related loan balances as of December 31, 2014Ending balance$242,311,000 $30,932,000 $104,531,000$20,424,000$384,032,000 $12,160,000 $103,521,000$19,653,000$—$917,564,000Ending balance specifically evaluated for impairment$13,304,000 $1,380,000 $2,942,000$—$16,123,000 $— $2,087,000$26,000$—$35,862,000Ending balance collectively evaluated for impairment$229,007,000 $29,552,000 $101,589,000$20,424,000$367,909,000 $12,160,000 $101,434,000$19,627,000$—$881,702,000The following table presents allowance for loan losses activity by class for the three months ended March 31, 2014, and allowance for loan loss balances by class and related loan balances by class as of March 31, 2014: CommercialMunicipalResidential Home Equity Line of CreditConsumerUnallocatedTotal Real EstateConstructionOther TermConstruction    For the three months ended March 31, 2014Beginning balance$4,602,000$575,000$2,276,000$15,000$1,099,000$21,000$675,000$573,000$1,678,000$11,514,000Charge offs20,000—174,000—119,000—12,00070,000—395,000Recoveries1,000—64,000—4,000—1,00066,000—136,000Provision (credit)(83,000)15,00075,000—248,0001,00044,000(52,000)152,000400,000Ending balance$4,500,000$590,000$2,241,000$15,000$1,232,000$22,000$708,000$517,000$1,830,000$11,655,000Allowance for loan losses as of March 31, 2014Ending balance specifically evaluated for impairment$1,019,000$276,000$834,000$—$574,000$—$83,000$—$—$2,786,000Ending balance collectively evaluated for impairment$3,481,000$314,000$1,407,000$15,000$658,000$22,000$625,000$517,000$1,830,000$8,869,000Related loan balances as of March 31, 2014Ending balance$240,187,000$21,686,000$97,276,000$17,790,000$372,479,000$12,360,000$92,202,000$14,934,000$—$868,914,000Ending balance specifically evaluated for impairment$15,260,000$1,492,000$5,258,000$—$16,924,000$—$1,653,000$—$—$40,587,000Ending balance collectively evaluated for impairment$224,927,000$20,194,000$92,018,000$17,790,000$355,555,000$12,360,000$90,549,000$14,934,000$—$828,327,000 |

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| - Definition
Tabular disclosure for the roll forward of change in allowance for loan losses from period to period and related loan balances.
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No definition available.
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| - Definition
Tabular disclosure of financing receivables (examples of financing receivables include loans, trade accounts receivable and notes receivable) and activity in the allowance for credit losses account.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524
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| - Definition
Tabular disclosure of financing receivables by credit quality indicator. The credit quality indicator is a statistic about the credit quality of financing receivables. Examples include, but not limited to, consumer credit risk scores, credit-rating-agency ratings, an entity's internal credit risk grades, loan-to-value ratios, collateral, collection experience and other internal metrics.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953659-111524Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 55 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=32702940&loc=SL6953803-111525
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