| **Preferred and Common Stock**           | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Stockholders' Equity Note [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Preferred and Common Stock               | Preferred and Common StockPreferred StockOn January 9, 2009, the Company issued $25,000,000 in Fixed Rate Cumulative Perpetual Preferred Stock, Series A, having a liquidation preference of $1,000 per share, to the U.S. Treasury under the Capital Purchase Program ("the CPP Shares"). The CPP Shares called for cumulative dividends at a rate of 5.0% per year for the first 5 years, and at a rate of 9.0% per year in following years, payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year.On August 24, 2011, the Company repurchased $12,500,000 of the CPP Shares.  Almost all of the repayment was made from retained earnings accumulated since the preferred stock was issued in 2009. On March 27, 2013, the Companyrepurchased $2,500,000 of the CPP Shares with funds from its operating account. On May 8, 2013, the Company repurchasedthe remaining $10,000,000 of the CPP Shares using proceeds from the Company's common stock offering in the first quarter of 2013, All the repurchase transactions were approved by the Federal Reserve Bank of Boston, the Company's primary regulator.Incident to such issuance, the Company issued to the U.S. Treasury warrants (the "Warrants") to purchase up to 225,904 shares of the Company's common stock at a price per share of $16.60 (subject to adjustment).  The Warrants (and any shares of common stock issuable pursuant to the Warrants) are freely transferable by Treasury to third parties and the Company has filed a registration statement with the Securities and Exchange Commission to allow for possible resale of such securities. The Warrants have a term of ten years and could be exercised by Treasury or a subsequent holder at any time or from time to time during their term. To the extent they had not previously been exercised, the Warrants would expire after 10 years. Treasury will not vote any shares of common stock it receives upon exercise of the Warrants, but that restriction would not apply to third parties to whom Treasury transferred the Warrants. The Warrants (and any common stock issued upon exercise of the Warrants) could be transferred to third parties separately from the CPP Shares. The proceeds from the sale of the CPP Shares were allocated between the CPP Shares and Warrants based on their relative fair values on the issue date. The fair value of the Warrants was determined using the Black-Scholes model which includes the following assumptions: common stock price of $16.60 per share, dividend yield of 4.70%, stock price volatility of 24.43%, and a risk-free interest rate of 2.01%. The discount on the CPP Shares was based on the value that was allocated to the Warrants upon issuance, and is being accreted back to the value of the CPP Shares over a five-year period (the expected life of the shares upon issuance) on a straight-line basis. The Warrants were unchanged as a result of the CPP Shares repurchase transaction and remain outstanding.Common StockThe Company has reserved 700,000 shares of its common stock to be made available to directors and employees who elect to participate in the stock purchase or savings and investment plans. As of December 31, 2013, 533,796 shares had been issued pursuant to these plans, leaving 166,204 shares available for future use. The issuance price is based on the market price of the stock at issuance date. Sales of stock to directors and employees amounted to 11,385 shares in 2013, 12,451 shares in 2012, and 12,775 shares in 2011.In 2001, the Company established a dividend reinvestment plan to allow shareholders to use their cash dividends for the automatic purchase of shares in the Company. When the plan was established, 600,000 shares were registered with the Securities and Exchange Commission, and as of December 31, 2013, 212,588 shares have been issued, leaving 387,412 shares for future use. Participation in this plan is optional and at the individual discretion of each Shareholder. Shares are purchased for the plan from the Company at a price per share equal to the average of the daily bid and asked prices reported on the NASDAQ System for the five trading days immediately preceding, but not including, the dividend payment date. Sales of stock under the Dividend Reinvestment Plan amounted to 12,008 shares in 2013, 14,056 shares in 2012, and 14,387 shares in 2011.      On March 28, 2013, the Company consummated a fully underwritten offering for 760,771 shares of the Company's common stock, with net proceeds of $11,649,000. The Company used these proceeds to repurchase the remaining $10,000,000 of CPP Shares on May 8, 2013. |

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| - Definition
The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.
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