<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:bgx="http://blackstone.com/20260630"
  xmlns:cef="http://xbrl.sec.gov/cef/2026"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
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    <link:schemaRef xlink:href="bgx-20260630.xsd" xlink:type="simple"/>
    <context id="From2026-01-01to2026-06-30">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001504234</identifier>
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        <period>
            <startDate>2026-01-01</startDate>
            <endDate>2026-06-30</endDate>
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            <identifier scheme="http://www.sec.gov/CIK">0001504234</identifier>
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                <xbrldi:explicitMember dimension="us-gaap:StatementClassOfStockAxis">bgx:CommonSharesMember</xbrldi:explicitMember>
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        <period>
            <startDate>2026-01-01</startDate>
            <endDate>2026-06-30</endDate>
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    <context id="AsOf2026-06-30">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001504234</identifier>
        </entity>
        <period>
            <instant>2026-06-30</instant>
        </period>
    </context>
    <unit id="Shares">
        <measure>shares</measure>
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    <unit id="USDPShares">
        <divide>
            <unitNumerator>
                <measure>iso4217:USD</measure>
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            <unitDenominator>
                <measure>shares</measure>
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        </divide>
    </unit>
    <dei:AmendmentFlag contextRef="From2026-01-01to2026-06-30" id="Fact000003">false</dei:AmendmentFlag>
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    <dei:EntityCentralIndexKey contextRef="From2026-01-01to2026-06-30" id="Fact000005">0001504234</dei:EntityCentralIndexKey>
    <dei:DocumentType contextRef="From2026-01-01to2026-06-30" id="xdx2ixbrl0011">N-CSRS</dei:DocumentType>
    <dei:EntityRegistrantName contextRef="From2026-01-01to2026-06-30" id="Fact000012">Blackstone Long-Short Credit Income Fund</dei:EntityRegistrantName>
    <dei:DocumentPeriodEndDate contextRef="From2026-01-01to2026-06-30" id="Fact000013">2026-06-30</dei:DocumentPeriodEndDate>
    <cef:OutstandingSecurityTitleTextBlock
      contextRef="From2026-01-012026-06-30_custom_CommonSharesMember"
      id="Fact000014">COMMON SHARES</cef:OutstandingSecurityTitleTextBlock>
    <cef:OutstandingSecurityAuthorizedShares
      contextRef="From2026-01-012026-06-30_custom_CommonSharesMember"
      decimals="INF"
      id="Fact000015"
      unitRef="Shares">12708275</cef:OutstandingSecurityAuthorizedShares>
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      contextRef="AsOf2026-06-30"
      decimals="INF"
      id="Fact000016"
      unitRef="USDPShares">12.22</us-gaap:NetAssetValuePerShare>
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      contextRef="AsOf2026-06-30"
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    <cef:InvestmentObjectivesAndPracticesTextBlock contextRef="From2026-01-01to2026-06-30" id="Fact000018">&lt;p id="xdx_A89_ecef--InvestmentObjectivesAndPracticesTextBlock_zbhY1sZZV26k" style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;BGX&#x2019;s primary investment objective is to provide
current income, with a secondary objective of capital appreciation. BGX seeks to achieve its investment objectives by employing a dynamic
long-short strategy in a diversified portfolio of loans and fixed-income instruments of predominantly U.S. corporate issuers, including
first- and second-lien secured loans (&#x201c;Secured Loans&#x201d;) and high-yield corporate debt securities of varying maturities. BGX&#x2019;s
short positions, either directly or through the use of derivatives, may total up to 30% of such Fund&#x2019;s net assets.&lt;/p&gt;



&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;/p&gt;






&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;/p&gt;






&lt;p style="font: 14pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;/p&gt;


&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: right"&gt;&lt;/p&gt;









&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&#160;&lt;/p&gt;

&lt;p style="font: 11pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Senior Loans, Secured Loans and Senior Secured Loans are referred to collectively
as &#x201c;Loans&#x201d; throughout the Notes to Financial Statements.&lt;/p&gt;

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