<?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">0001860424</identifier>
        </entity>
        <period>
            <startDate>2026-07-10</startDate>
            <endDate>2026-07-10</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001860424</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-07-10</startDate>
            <endDate>2026-07-10</endDate>
        </period>
    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-150">SC TO</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-151">SC TO-I</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-152">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-153">0001860424</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-154">Onex Direct Lending BDC Fund</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
    <ffd:Rule011Flg contextRef="offrl_1" id="ixv-157">true</ffd:Rule011Flg>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-182">false</ffd:PrevslyPdFlg>
    <ffd:TxValtn
      contextRef="offrl_1"
      decimals="2"
      id="ixv-183"
      unitRef="USD">7910869.00</ffd:TxValtn>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-184"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-185"
      unitRef="USD">1092.49</ffd:FeeAmt>
    <ffd:TtlTxValtn contextRef="rc" decimals="2" id="ixv-186" unitRef="USD">7910869.00</ffd:TtlTxValtn>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-187" unitRef="USD">1092.49</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-188" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-189" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-190" unitRef="USD">1092.49</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-191">Estimated for purposes of calculating the amount of the filing fee only. Calculated as the aggregate maximum purchase price to be paid for 421,913 Shares in the offer, based upon the net asset value per share of $18.75 as of March 31, 2026. Calculated at $138.10 per $1,000,000 of the Transaction Valuation, pursuant to Rule 0-11 of the Securities Exchange Act of 1934, as amended.</ffd:OfferingNote>
</xbrl>
