<?xml version="1.0" encoding="utf-8"?>
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    <context id="c0">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001057706</identifier>
        </entity>
        <period>
            <startDate>2026-06-22</startDate>
            <endDate>2026-06-22</endDate>
        </period>
    </context>
    <context id="c1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001057706</identifier>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
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        <period>
            <startDate>2026-06-22</startDate>
            <endDate>2026-06-22</endDate>
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    <unit id="shares">
        <measure>shares</measure>
    </unit>
    <unit id="usdPershares">
        <divide>
            <unitNumerator>
                <measure>iso4217:USD</measure>
            </unitNumerator>
            <unitDenominator>
                <measure>shares</measure>
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    <unit id="usd">
        <measure>iso4217:USD</measure>
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    <unit id="pure">
        <measure>pure</measure>
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    <ffd:SubmissnTp contextRef="c0" id="ixv-162">S-8</ffd:SubmissnTp>
    <ffd:FormTp contextRef="c0" id="ixv-163">S-8</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="c0" id="ixv-27">FIRST BANCORP.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="c1" id="ixv-73">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c1" id="ixv-74">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c1" id="ixv-77">Common Stock, par value $0.10 per share</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="c1" id="ixv-80">true</ffd:FeesOthrRuleFlg>
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      contextRef="c1"
      decimals="INF"
      id="ixv-164"
      unitRef="shares">5000000</ffd:AmtSctiesRegd>
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      contextRef="c1"
      decimals="INF"
      id="ixv-165"
      unitRef="usdPershares">25.17</ffd:MaxOfferingPricPerScty>
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    <ffd:TtlOfferingAmt contextRef="c0" decimals="INF" id="ixv-169" unitRef="usd">125850000</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="c0" decimals="2" id="ixv-170" unitRef="usd">17379.89</ffd:TtlFeeAmt>
    <ffd:TtlOffsetAmt contextRef="c0" decimals="0" id="ixv-171" unitRef="usd">0</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="c0" decimals="2" id="ixv-172" unitRef="usd">17379.89</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="c1" id="ixv-120">&lt;table style="font-size: 12pt; border-spacing: 0px; border-collapse: collapse; width: 100%;"&gt; &lt;tr style="height: 0px; font-size: 0px;"&gt;&lt;td style="width: 1%;"&gt;&#160;&lt;/td&gt;&lt;td style="width: 99%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="vertical-align: top;"&gt; &lt;td style="padding: 0px 0pt;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; &lt;span style="font-size: 10.0pt;"&gt;(1)&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;td style="padding: 0px 5.4pt; text-align: justify;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; &lt;span style="font-size: 10.0pt;"&gt;&lt;span style="line-height: 115%;"&gt;Pursuant to Rule 416(2), this Registration
Statement on Form S-8 also covers any additional shares of Common Stock of the
Corporation that may be issues from time to time under the Plan as a result of
stock splits, recapitalization, or similar transactions involving the
Corporation&#x2019;s Common Stock in accordance with the anti-dilution provisions of
the Plan.&lt;/span&gt;&lt;/span&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;&lt;table style="font-size: 12pt; border-spacing: 0px; border-collapse: collapse; width: 100%;"&gt;
   &lt;tr style="height: 0px; font-size: 0px;"&gt;&lt;td style="width: 1%;"&gt;&#160;&lt;/td&gt;&lt;td style="width: 99%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="vertical-align: top;"&gt;
    &lt;td style="padding: 0px 0pt;"&gt;
     &lt;div style="margin-bottom: 4pt;"&gt;
      &lt;span style="font-size: 10.0pt;"&gt;(2)&lt;/span&gt;
     &lt;/div&gt;
    &lt;/td&gt;
    &lt;td style="padding: 0px 5.4pt; text-align: justify;"&gt;
     &lt;div style="margin-bottom: 4pt;"&gt;
      &lt;span style="font-size: 10.0pt;"&gt;&lt;span style="line-height: 115%;"&gt;Estimated in accordance with Rule 457(c) and
Rule 457(h) of the Securities Act solely for the purpose of calculating the registration
fee based upon the average of the high and low sale prices of the Corporation&#x2019;s
Common Stock as reported on The New York Stock Exchange on June 17, 2026.&lt;/span&gt;&lt;/span&gt;
     &lt;/div&gt;
    &lt;/td&gt;
   &lt;/tr&gt;
  &lt;/table&gt;</ffd:OfferingNote>
    <dei:EntityCentralIndexKey contextRef="c0" id="ixv-175">0001057706</dei:EntityCentralIndexKey>
    <ffd:FeeExhibitTp contextRef="c0" id="ixv-176">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:OffsetTableNa contextRef="c0" id="ixv-177">N/A</ffd:OffsetTableNa>
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