<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2025"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2025"
  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/2025/ffd-2025.xsd"
      xlink:type="simple"/>
    <context id="c_offering_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002083946</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
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        </entity>
        <period>
            <startDate>2025-12-31</startDate>
            <endDate>2025-12-31</endDate>
        </period>
    </context>
    <context id="c_offering_2">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002083946</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>2</dei:lineNo>
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        </entity>
        <period>
            <startDate>2025-12-31</startDate>
            <endDate>2025-12-31</endDate>
        </period>
    </context>
    <context id="c_offering_3">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002083946</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>3</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2025-12-31</startDate>
            <endDate>2025-12-31</endDate>
        </period>
    </context>
    <context id="c_offering_4">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002083946</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>4</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2025-12-31</startDate>
            <endDate>2025-12-31</endDate>
        </period>
    </context>
    <context id="c_report">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002083946</identifier>
        </entity>
        <period>
            <startDate>2025-12-31</startDate>
            <endDate>2025-12-31</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:SubmissnTp contextRef="c_report" id="fee_001">S-1</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="c_report" id="fee_002">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="c_report" id="fee_003">0002083946</dei:EntityCentralIndexKey>
    <ffd:OfferingTableNa contextRef="c_report" id="fee_004" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="c_report" id="fee_005">N/A</ffd:OffsetTableNa>
    <ffd:CombinedProspectusTableNa contextRef="c_report" id="fee_006">N/A</ffd:CombinedProspectusTableNa>
    <ffd:FormTp contextRef="c_report" id="fee_007">S-1</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="c_report" id="fee_008">Willow Lane Acquisition Corp. II</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="c_offering_1" id="fee_009">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c_offering_1" id="fee_010">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c_offering_1" id="fee_011">Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-fourth of one redeemable warrant</ffd:OfferingSctyTitl>
    <ffd:Rule457aFlg contextRef="c_offering_1" id="fee_012">true</ffd:Rule457aFlg>
    <ffd:AmtSctiesRegd
      contextRef="c_offering_1"
      decimals="0"
      id="fee_013"
      unitRef="shares">14375000</ffd:AmtSctiesRegd>
    <ffd:MaxOfferingPricPerScty
      contextRef="c_offering_1"
      decimals="INF"
      id="fee_014"
      unitRef="USD">10.00</ffd:MaxOfferingPricPerScty>
    <ffd:MaxAggtOfferingPric
      contextRef="c_offering_1"
      decimals="INF"
      id="fee_015"
      unitRef="USD">143750000.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="c_offering_1"
      decimals="INF"
      id="fee_016"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="c_offering_1"
      decimals="INF"
      id="fee_017"
      unitRef="USD">19851.88</ffd:FeeAmt>
    <ffd:PrevslyPdFlg contextRef="c_offering_2" id="fee_018">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c_offering_2" id="fee_019">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c_offering_2" id="fee_020">Class A ordinary shares included as part of the units</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="c_offering_2" id="fee_021">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="c_offering_2"
      decimals="0"
      id="fee_022"
      unitRef="shares">14375000</ffd:AmtSctiesRegd>
    <ffd:FeeRate
      contextRef="c_offering_2"
      decimals="INF"
      id="fee_023"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="c_offering_2"
      decimals="INF"
      id="fee_024"
      unitRef="USD">0.00</ffd:FeeAmt>
    <ffd:PrevslyPdFlg contextRef="c_offering_3" id="fee_025">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c_offering_3" id="fee_026">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c_offering_3" id="fee_027">Redeemable warrants included as part of the units</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="c_offering_3" id="fee_028">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="c_offering_3"
      decimals="0"
      id="fee_029"
      unitRef="shares">3593750</ffd:AmtSctiesRegd>
    <ffd:FeeRate
      contextRef="c_offering_3"
      decimals="INF"
      id="fee_030"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="c_offering_3"
      decimals="INF"
      id="fee_031"
      unitRef="USD">0.00</ffd:FeeAmt>
    <ffd:PrevslyPdFlg contextRef="c_offering_4" id="fee_032">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c_offering_4" id="fee_033">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c_offering_4" id="fee_034">Class A ordinary shares underlying redeemable warrants included as part of the units</ffd:OfferingSctyTitl>
    <ffd:Rule457aFlg contextRef="c_offering_4" id="fee_035">true</ffd:Rule457aFlg>
    <ffd:AmtSctiesRegd
      contextRef="c_offering_4"
      decimals="0"
      id="fee_036"
      unitRef="shares">3593750</ffd:AmtSctiesRegd>
    <ffd:MaxOfferingPricPerScty
      contextRef="c_offering_4"
      decimals="INF"
      id="fee_037"
      unitRef="USD">11.50</ffd:MaxOfferingPricPerScty>
    <ffd:MaxAggtOfferingPric
      contextRef="c_offering_4"
      decimals="INF"
      id="fee_038"
      unitRef="USD">41328125.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="c_offering_4"
      decimals="INF"
      id="fee_039"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="c_offering_4"
      decimals="INF"
      id="fee_040"
      unitRef="USD">5707.41</ffd:FeeAmt>
    <ffd:TtlOfferingAmt
      contextRef="c_report"
      decimals="INF"
      id="fee_041"
      unitRef="USD">185078125.00</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt
      contextRef="c_report"
      decimals="INF"
      id="fee_042"
      unitRef="USD">25559.29</ffd:TtlFeeAmt>
    <ffd:NetFeeAmt
      contextRef="c_report"
      decimals="INF"
      id="fee_043"
      unitRef="USD">25559.29</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="c_offering_1" id="fee_044">Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(a) of the Securities Act.&lt;br/&gt;&lt;br/&gt;Each unit consists of one Class A ordinary share, $0.0001 par value, and one-fourth of a redeemable warrant (&#x201c;Warrants&#x201d;) each whole Warrant exercisable for $11.50 to purchase one Class A ordinary share.&lt;br/&gt;&lt;br/&gt;Includes 1,875,000 units, which may be issued upon exercise of a 45-day option granted to the underwriters to cover over-allotments, if any.&lt;br/&gt;</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="c_offering_2" id="fee_045">Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(a) of the Securities Act.&lt;br/&gt;&lt;br/&gt;No fee pursuant to 457(g).&lt;br/&gt;</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="c_offering_3" id="fee_046">Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(a) of the Securities Act.&lt;br/&gt;&lt;br/&gt;No fee pursuant to 457(g).</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="c_offering_4" id="fee_047">Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(a).&lt;br/&gt;&lt;br/&gt;Pursuant to Rule 416, there are also being registered an indeterminable number of additional securities as may be issued to prevent dilution resulting from share splits, share dividends or similar transactions.</ffd:OfferingNote>
</xbrl>
