<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2026"
  xmlns:iso4217="http://www.xbrl.org/2003/iso4217"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xbrldi="http://xbrl.org/2006/xbrldi"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <link:schemaRef
      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
      xlink:type="simple"/>
    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001947463</identifier>
        </entity>
        <period>
            <startDate>2026-07-29</startDate>
            <endDate>2026-07-29</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001947463</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-07-29</startDate>
            <endDate>2026-07-29</endDate>
        </period>
    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-351">S-4</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-352">S-4</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-353">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-354">0001947463</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-355">ODNB Financial Corp</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
    <ffd:CombinedProspectusTableNa contextRef="rc" id="hiddenrcCombinedProspectusTableNa">N/A</ffd:CombinedProspectusTableNa>
    <ffd:FormTp contextRef="rc" id="ixv-383">S-4</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-384">ODNB Financial Corp</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-385">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-386">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-387">Common Stock, $0.25 par value</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="offrl_1" id="ixv-388">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="offrl_1"
      decimals="0"
      id="ixv-389"
      unitRef="Shares">6037400</ffd:AmtSctiesRegd>
    <ffd:MaxAggtOfferingPric
      contextRef="offrl_1"
      decimals="2"
      id="ixv-390"
      unitRef="USD">92191040.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-391"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-392"
      unitRef="USD">12731.58</ffd:FeeAmt>
    <ffd:TtlOfferingAmt contextRef="rc" decimals="2" id="ixv-393" unitRef="USD">92191040.00</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-394" unitRef="USD">12731.58</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-395" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-396" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-397" unitRef="USD">12731.58</ffd:NetFeeAmt>
    <ffd:Rule457fFlg contextRef="offrl_1" id="ixv-398">true</ffd:Rule457fFlg>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-399">The amount in the "Amount Registered" column represents the maximum number of shares of ODNB Financial Corporation ("ODNB") common stock, $0.25 par value per share, to be issuable upon completion of the merger by and between ODNB and National Capital Bancorp, Inc. ("NACB") described in the enclosed joint proxy statement/prospectus and the merger agreement. 

The amount in the "Maximum Aggregate Offering Price" column is estimated solely for the purpose of calculating the registration fee as required by Section 6(b) of the Securities Act of 1933, as amended, and calculated pursuant to Rule 457(f)(1) promulgated thereunder. NACB common shares are traded on the OTC Market Group's OTCID Basic Market. Therefore, the maximum aggregate offering price has been calculated as the product of (i) $80.00, the average of the bid and asked price per NACB common share as reported on the OTC Market Group's OTCID Basic Market as of July 27, 2026, and (ii) 1,152,388, the number of NACB common shares to be exchanged in the merger.

Calculated by multiplying the estimated aggregate offering price of securities to be registered by 0.0001381.</ffd:OfferingNote>
    <ffd:AmtSctiesRcvd
      contextRef="offrl_1"
      decimals="0"
      id="ixv-400"
      unitRef="Shares">1152388</ffd:AmtSctiesRcvd>
    <ffd:ValSctiesRcvdPerShr
      contextRef="offrl_1"
      decimals="2"
      id="ixv-401"
      unitRef="USD">80.00</ffd:ValSctiesRcvdPerShr>
    <ffd:ValSctiesRcvd
      contextRef="offrl_1"
      decimals="2"
      id="ixv-402"
      unitRef="USD">92191040.00</ffd:ValSctiesRcvd>
    <ffd:FeeNoteMaxAggtOfferingPric
      contextRef="offrl_1"
      decimals="2"
      id="ixv-403"
      unitRef="USD">92191040.00</ffd:FeeNoteMaxAggtOfferingPric>
</xbrl>
