Basis Of Presentation	3 Months Ended
Mar. 31, 2012
Basis Of Presentation [Abstract]
BASIS OF PRESENTATION	NOTE 1: BASIS OF PRESENTATION The accompanying unaudited consolidated financial statements of DNB Financial Corporation (referred to herein as the "Corporation" or "DNB") and its subsidiary, DNB First, National Association (the "Bank") have been prepared in accordance with the instructions for Form 10-Q and therefore do not include certain information or footnotes necessary for the presentation of financial condition, statement of operations and statement of cash flows required by generally accepted accounting principles. However, in the opinion of management, the consolidated financial statements reflect all adjustments (which consist of normal recurring adjustments) necessary for a fair presentation of the results for the unaudited periods. Prior amounts not affecting net income are reclassified when necessary to conform to current period classifications. The results of operations for the three month period ended March 31, 2012 are not necessarily indicative of the results which may be expected for the entire year. The consolidated financial statements should be read in conjunction with the Annual Report and report on Form 10-K for the year ended December 31, 2011. Subsequent Events-- Management has evaluated events and transactions occurring subsequent to March 31, 2012 for items that should potentially be recognized or disclosed in these Consolidated Financial Statements. The evaluation was conducted through the date these financial statements were issued. On April 2, 2012, DNB First, National Association (the "Bank"), the wholly owned subsidiary of DNB Financial Corporation, entered into a Purchase and Assumption Agreement, dated as of April 2, 2012, with Capital Bank, N.A ("Capital Bank") (the "Agreement") to acquire certain assets and assume certain liabilities of one full-service branch office of Capital Bank located at 3915 Chichester Avenue, Boothwyn, Pennsylvania (the "Branch Acquisition"). Under the terms of the Agreement, the Bank will purchase specified assets of the branch, including real estate, furniture and equipment and approximately $17 million of total deposits. The Branch Acquisition includes the payment of a 0.82% premium on total deposits. Additionally, the Branch Acquisition is subject to customary closing conditions, including receipt of applicable regulatory approvals. The Bank intends to consummate the Branch Acquisition during the second quarter of 2012. At DNB's Annual Meeting on April 25, 2011, shareholders approved the Board of Directors' recommendation to amend and restate the DNB Financial Corporation Amended and Restated 1995 Stock Option Plan. These amendments increased the amount of shares available for grant under the Plan by 150,000 shares and extended the Plan term by approximately eight years to April 25, 2022.

NOTE 1: BASIS OF PRESENTATION

The accompanying unaudited consolidated financial statements of DNB Financial Corporation (referred to herein as the "Corporation" or "DNB") and its subsidiary, DNB First, National Association (the "Bank") have been prepared in accordance with the instructions for Form 10-Q and therefore do not include certain information or footnotes necessary for the presentation of financial condition, statement of operations and statement of cash flows required by generally accepted accounting principles. However, in the opinion of management, the consolidated financial statements reflect all adjustments (which consist of normal recurring adjustments) necessary for a fair presentation of the results for the unaudited periods. Prior amounts not affecting net income are reclassified when necessary to conform to current period classifications. The results of operations for the three month period ended March 31, 2012 are not necessarily indicative of the results which may be expected for the entire year. The consolidated financial statements should be read in conjunction with the Annual Report and report on Form 10-K for the year ended December 31, 2011.

Subsequent Events-- Management has evaluated events and transactions occurring subsequent to March 31, 2012 for items that should potentially be recognized or disclosed in these Consolidated Financial Statements. The evaluation was conducted through the date these financial statements were issued.

On April 2, 2012, DNB First, National Association (the "Bank"), the wholly owned subsidiary of DNB Financial Corporation, entered into a Purchase and Assumption Agreement, dated as of April 2, 2012, with Capital Bank, N.A ("Capital Bank") (the "Agreement") to acquire certain assets and assume certain liabilities of one full-service branch office of Capital Bank located at 3915 Chichester Avenue, Boothwyn, Pennsylvania (the "Branch Acquisition"). Under the terms of the Agreement, the Bank will purchase specified assets of the branch, including real estate, furniture and equipment and approximately $17 million of total deposits. The Branch Acquisition includes the payment of a 0.82% premium on total deposits. Additionally, the Branch Acquisition is subject to customary closing conditions, including receipt of applicable regulatory approvals. The Bank intends to consummate the Branch Acquisition during the second quarter of 2012.

At DNB's Annual Meeting on April 25, 2011, shareholders approved the Board of Directors' recommendation to amend and restate the DNB Financial Corporation Amended and Restated 1995 Stock Option Plan. These amendments increased the amount of shares available for grant under the Plan by 150,000 shares and extended the Plan term by approximately eight years to April 25, 2022.