<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:fnd="http://xbrl.sec.gov/fnd/2026q3"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xlink="http://www.w3.org/1999/xlink">
    <link:schemaRef xlink:href="ft13307-20261023.xsd" xlink:type="simple"/>
    <context id="AsOf2026-10-23">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0002148635</identifier>
        </entity>
        <period>
            <startDate>2026-10-23</startDate>
            <endDate>2026-10-23</endDate>
        </period>
    </context>
    <dei:AmendmentFlag contextRef="AsOf2026-10-23" id="Fact000003">true</dei:AmendmentFlag>
    <dei:AmendmentDescription contextRef="AsOf2026-10-23" id="Fact000004">Amended to include final prospectus for SEC review.</dei:AmendmentDescription>
    <dei:EntityCentralIndexKey contextRef="AsOf2026-10-23" id="Fact000005">0002148635</dei:EntityCentralIndexKey>
    <dei:DocumentType contextRef="AsOf2026-10-23" id="Fact000011">S-6</dei:DocumentType>
    <dei:EntityRegistrantName contextRef="AsOf2026-10-23" id="Fact000012">FT 13307</dei:EntityRegistrantName>
    <dei:DocumentPeriodEndDate contextRef="AsOf2026-10-23" id="Fact000013">2026-10-23</dei:DocumentPeriodEndDate>
    <fnd:NmRule35d1TermDfnTextBlock contextRef="AsOf2026-10-23" id="Fact000014">

&lt;p style="font: bold 11pt/12pt Times New Roman, Times, Serif; margin: 4pt 0 1pt"&gt;Objective.&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;The
Trust seeks above-average total return through a combination of capital appreciation and dividend income. Under normal circumstances,
the Trust will invest at least 80% of its assets in &#x201c;Dividend Leaders&#x201d; that are headquartered or incorporated in the United
States. The Sponsor defines &#x201c;Dividend Leaders&#x201d; as the top 30 companies as determined by the ranking process described below.
The Trust is concentrated (i.e., invests 25% or more of Trust assets) in common stocks of companies within the financials sector.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</fnd:NmRule35d1TermDfnTextBlock>
    <fnd:NmRule35d1TermSlctnCritTextBlock contextRef="AsOf2026-10-23" id="Fact000015">

&lt;p style="font: bold 11pt/12pt Times New Roman, Times, Serif; margin: 4pt 0 1pt"&gt;Portfolio Selection Process.&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;Through
our selection process we seek to find financially healthy, dividend-paying companies headquartered or incorporated in the United States
that we believe have the best prospects for above-average total return. &lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&lt;i&gt;Identify
the Universe&lt;/i&gt;. We begin with all stocks of companies headquartered or incorporated in the United States with a market capitalization
greater than $1 billion. We then eliminate any regulated investment companies, limited partnerships, and real estate investment trusts
(&#x201c;REITs&#x201d;), including mortgage REITs. &lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&lt;i&gt;Screen
for Financial Strength.&lt;/i&gt; The next step is to look for those companies that meet the following criteria: &lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt/11pt Times New Roman, Times, Serif; width: 100%; margin-top: 0; margin-bottom: 2pt"&gt;&lt;tr style="vertical-align: top"&gt;
&lt;td style="width: 0"&gt;&lt;/td&gt;&lt;td style="width: 10pt"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#x2022;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="letter-spacing: -0.05pt"&gt;Three-month average daily trading volume greater than $5 million; &lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt/11pt Times New Roman, Times, Serif; width: 100%; margin-top: 0; margin-bottom: 2pt"&gt;&lt;tr style="vertical-align: top"&gt;
&lt;td style="width: 0"&gt;&lt;/td&gt;&lt;td style="width: 10pt"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#x2022;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="letter-spacing: -0.05pt"&gt;Payout ratio greater than 0% and less than 100%;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt/11pt Times New Roman, Times, Serif; width: 100%; margin-top: 0; margin-bottom: 2pt"&gt;&lt;tr style="vertical-align: top"&gt;
&lt;td style="width: 0"&gt;&lt;/td&gt;&lt;td style="width: 10pt"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#x2022;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="letter-spacing: -0.05pt"&gt;Financial companies must have positive earnings per share over the last 12 months; &lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt/11pt Times New Roman, Times, Serif; width: 100%; margin-top: 0; margin-bottom: 2pt"&gt;&lt;tr style="vertical-align: top"&gt;
&lt;td style="width: 0"&gt;&lt;/td&gt;&lt;td style="width: 10pt"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#x2022;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="letter-spacing: -0.05pt"&gt;All other companies must have a free cash flow yield greater than zero; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt/11pt Times New Roman, Times, Serif; width: 100%; margin-top: 0; margin-bottom: 2pt"&gt;&lt;tr style="vertical-align: top"&gt;
&lt;td style="width: 0"&gt;&lt;/td&gt;&lt;td style="width: 10pt"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&#x2022;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="letter-spacing: -0.05pt"&gt;Debt-to-equity must be less than or equal to one. &lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;&lt;i&gt;Select
Companies.&lt;/i&gt; The final step in our process is to select the top 30 companies ranked by current indicated dividend yield, excluding one-time
special dividends, as of two business days prior to the Initial Date of Deposit. The selected securities are weighted by their trailing
12 months absolute dividends paid subject to the restriction that the total weight of all securities above 5% cannot exceed half of the
portfolio&#x2019;s weight. Shares of securities-related issuers will not exceed approximately 4% of the portfolio on the Initial Date of
Deposit. &lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;While
not a part of the Trust&#x2019;s portfolio selection process, the Trust also invests in foreign securities and companies with various market
capitalizations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt/11pt Times New Roman, Times, Serif; margin: 0 0 2pt; text-indent: 0.25in"&gt;&lt;span style="letter-spacing: -0.05pt"&gt;As
with any similar investments, there can be no assurance that the objective of the Trust will be achieved. See &#x201c;Risk Factors&#x201d;
for a discussion of the risks of investing in the Trust.&lt;/span&gt;&lt;/p&gt;

</fnd:NmRule35d1TermSlctnCritTextBlock>
</xbrl>
