Basis Of Presentation	9 Months Ended
Sep. 30, 2015
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 and nine months ended September 30, 2015 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, 2014. Subsequent Events-- Management has evaluated events and transactions occurring subsequent to September 30, 2015 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. Recent Accounting Pronouncements- In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contract with Customers (Topic 606). The guidance in this update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following five steps: 1) identify the contracts(s) with the customer; 2) identify the performance obligations in the contract; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations in the contract; and 5) recognize revenue when (or as) the entity satisfies a performance obligation. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. For a public entity, the amendments in this update are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. DNB is still evaluating the effect of this amendment on DNB's consolidated financial statements. In June 2014, ASU No. 2014-11 amended ASC Topic 860, “Transfers and Servicing” to address concerns that current accounting guidance distinguishes between repurchase agreements that settle at the same time as the maturity of the transferred financial asset and those that settle any time before maturity. The update changed the accounting for repurchase-to-maturity transactions to secured borrowing accounting and, for repurchase financing arrangements, separate accounting for a transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty, which resulted in secured borrowing accounting for the repurchase agreement. The adoption of this ASU did not have a material effect on DNB’s operating results or financial condition. In April 2015, the FASB issued ASU No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The update simplifies the presentation of debt issuance costs by requiring that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts or premiums. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this update. For public companies, this update will be effective for interim and annual periods beginning after December 15, 2015, and is to be applied retrospectively. Early adoption is permitted. DNB is currently assessing the impact that this guidance will have on its consolidated financial statements, but does not expect the guidance to have a material impact on the DNB's consolidated financial statements.

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 and nine months ended September 30, 2015 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, 2014.

Subsequent Events-- Management has evaluated events and transactions occurring subsequent to September 30, 2015 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.

Recent Accounting Pronouncements-

In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contract with Customers (Topic 606). The guidance in this update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following five steps: 1) identify the contracts(s) with the customer; 2) identify the performance obligations in the contract; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations in the contract; and 5) recognize revenue when (or as) the entity satisfies a performance obligation. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. For a public entity, the amendments in this update are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. DNB is still evaluating the effect of this amendment on DNB's consolidated financial statements.

In June 2014, ASU No. 2014-11 amended ASC Topic 860, “Transfers and Servicing” to address concerns that current accounting guidance distinguishes between repurchase agreements that settle at the same time as the maturity of the transferred financial asset and those that settle any time before maturity. The update changed the accounting for repurchase-to-maturity transactions to secured borrowing accounting and, for repurchase financing arrangements, separate accounting for a transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty, which resulted in secured borrowing accounting for the repurchase agreement. The adoption of this ASU did not have a material effect on DNB’s operating results or financial condition.

In April 2015, the FASB issued ASU No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The update simplifies the presentation of debt issuance costs by requiring that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts or premiums. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this update. For public companies, this update will be effective for interim and annual periods beginning after December 15, 2015, and is to be applied retrospectively. Early adoption is permitted. DNB is currently assessing the impact that this guidance will have on its consolidated financial statements, but does not expect the guidance to have a material impact on the DNB's consolidated financial statements.