<?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">
    <link:schemaRef
      xlink:href="https://xbrl.sec.gov/ffd/2025/ffd-2025.xsd"
      xlink:type="simple"/>
    <context id="c0">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001531193</identifier>
        </entity>
        <period>
            <startDate>2026-06-08</startDate>
            <endDate>2026-06-08</endDate>
        </period>
    </context>
    <context id="c1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001531193</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-06-08</startDate>
            <endDate>2026-06-08</endDate>
        </period>
    </context>
    <context id="c2">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001531193</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>2</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-06-08</startDate>
            <endDate>2026-06-08</endDate>
        </period>
    </context>
    <unit id="shares">
        <measure>shares</measure>
    </unit>
    <unit id="usdPershares">
        <divide>
            <unitNumerator>
                <measure>iso4217:USD</measure>
            </unitNumerator>
            <unitDenominator>
                <measure>shares</measure>
            </unitDenominator>
        </divide>
    </unit>
    <unit id="usd">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <ffd:FormTp contextRef="c0" id="ixv-16">S-1</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="c0" id="ixv-25">First Carolina Financial Services, Inc.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="c1" id="ixv-215">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c1" id="ixv-216">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c1" id="ixv-217">Common stock, $0.50 par value per share</ffd:OfferingSctyTitl>
    <ffd:Rule457aFlg contextRef="c1" id="ixv-218">true</ffd:Rule457aFlg>
    <ffd:AmtSctiesRegd
      contextRef="c1"
      decimals="INF"
      id="ixv-219"
      unitRef="shares">75000</ffd:AmtSctiesRegd>
    <ffd:MaxOfferingPricPerScty
      contextRef="c1"
      decimals="INF"
      id="ixv-220"
      unitRef="usdPershares">16</ffd:MaxOfferingPricPerScty>
    <ffd:MaxAggtOfferingPric contextRef="c1" decimals="INF" id="ixv-221" unitRef="usd">1200000</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate contextRef="c1" decimals="INF" id="ixv-222" unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt contextRef="c1" decimals="2" id="ixv-223" unitRef="usd">165.72</ffd:FeeAmt>
    <ffd:PrevslyPdFlg contextRef="c2" id="ixv-224">true</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c2" id="ixv-225">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c2" id="ixv-226">Common stock, $0.50 par value per share</ffd:OfferingSctyTitl>
    <ffd:Rule457aFlg contextRef="c2" id="ixv-227">true</ffd:Rule457aFlg>
    <ffd:AmtSctiesRegd
      contextRef="c2"
      decimals="INF"
      id="ixv-228"
      unitRef="shares">6250000</ffd:AmtSctiesRegd>
    <ffd:MaxOfferingPricPerScty
      contextRef="c2"
      decimals="INF"
      id="ixv-229"
      unitRef="usdPershares">16</ffd:MaxOfferingPricPerScty>
    <ffd:MaxAggtOfferingPric contextRef="c2" decimals="INF" id="ixv-230" unitRef="usd">100000000</ffd:MaxAggtOfferingPric>
    <ffd:FeeAmt contextRef="c2" decimals="2" id="ixv-231" unitRef="usd">13810</ffd:FeeAmt>
    <ffd:TtlOfferingAmt contextRef="c0" decimals="INF" id="ixv-232" unitRef="usd">101200000</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="c0" decimals="2" id="ixv-233" unitRef="usd">13975.72</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="c0" decimals="2" id="ixv-234" unitRef="usd">13810</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="c0" decimals="2" id="ixv-235" unitRef="usd">0</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="c0" decimals="2" id="ixv-236" unitRef="usd">165.72</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="c1" id="ixv-187">&lt;table style="border-spacing: 0px; border-collapse: collapse; width: 100%; font-size: 10pt;"&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; 1&lt;/div&gt; &lt;/td&gt; &lt;td style="padding: 0px 5.4pt; text-align: left;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; 1a. Includes the aggregate offering price of additional shares that the underwriters have the option to purchase to cover over-allotments, if any. &lt;br/&gt;1b. Estimated solely for the purpose of calculating the registration fee in accordance with Rule 457(a) under the Securities Act of 1933, as amended.&lt;br/&gt; &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="c2" id="ixv-199">&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; font-size: 10pt;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; 2 &lt;/div&gt; &lt;/td&gt; &lt;td style="padding: 0px 5.4pt; text-align: left; font-size: 10pt;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; 2a. See note 1a. &lt;br/&gt;2b. See note 1b. &lt;br/&gt;2c. This Maximum Aggregate Offering Price was originally registered under 457(o) and is now converted to 457(a). &lt;/div&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt;</ffd:OfferingNote>
    <ffd:CombinedProspectusTableNa contextRef="c0" id="ixv-239">N/A</ffd:CombinedProspectusTableNa>
    <dei:EntityCentralIndexKey contextRef="c0" id="ixv-240">0001531193</dei:EntityCentralIndexKey>
    <ffd:FeeExhibitTp contextRef="c0" id="ixv-241">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:OffsetTableNa contextRef="c0" id="ixv-242">N/A</ffd:OffsetTableNa>
    <ffd:RegnFileNb contextRef="c0" id="ixv-243">333-296151</ffd:RegnFileNb>
    <ffd:SubmissnTp contextRef="c0" id="ixv-244">S-1/A</ffd:SubmissnTp>
</xbrl>
