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  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2025"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2025"
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      xlink:href="https://xbrl.sec.gov/ffd/2025/ffd-2025.xsd"
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    <context id="c0">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001163668</identifier>
        </entity>
        <period>
            <startDate>2026-01-30</startDate>
            <endDate>2026-01-30</endDate>
        </period>
    </context>
    <context id="c1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001163668</identifier>
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        <period>
            <startDate>2026-01-30</startDate>
            <endDate>2026-01-30</endDate>
        </period>
    </context>
    <unit id="shares">
        <measure>shares</measure>
    </unit>
    <unit id="usd">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
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    <ffd:FormTp contextRef="c0" id="ixv-247">S-4</ffd:FormTp>
    <ffd:SubmissnTp contextRef="c0" id="ixv-248">S-4</ffd:SubmissnTp>
    <dei:EntityRegistrantName contextRef="c0" id="ixv-25">South Plains Financial, Inc.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="c1" id="ixv-249">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c1" id="ixv-250">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="c1" id="ixv-251">Common stock, $1.00 par value per share</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="c1" id="ixv-252">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="c1"
      decimals="INF"
      id="ixv-253"
      unitRef="shares">2767808</ffd:AmtSctiesRegd>
    <ffd:MaxAggtOfferingPric contextRef="c1" decimals="INF" id="ixv-254" unitRef="usd">76779689.46</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate contextRef="c1" decimals="7" id="ixv-255" unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt contextRef="c1" decimals="2" id="ixv-256" unitRef="usd">10603.28</ffd:FeeAmt>
    <ffd:TtlOfferingAmt contextRef="c0" decimals="INF" id="ixv-257" unitRef="usd">76779689.46</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="c0" decimals="2" id="ixv-258" unitRef="usd">10603.28</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="c0" decimals="2" id="ixv-259" unitRef="usd">0</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="c0" decimals="2" id="ixv-260" unitRef="usd">0</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="c0" decimals="2" id="ixv-261" unitRef="usd">10603.28</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="c1" id="ixv-203">&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: left;"&gt; &lt;div style="margin-bottom: 4pt;"&gt; &lt;span style="font-size: 10.0pt;"&gt;Represents the maximum number of shares of South Plains Financial, Inc.
(&#x201c;SPFI&#x201d;) common stock, par value $1.00 per
share (&#x201c;SPFI common stock&#x201d;) to be issuable
upon completion of the merger described herein. This number is based on the
product of (a) an exchange ratio of 0.1925 shares of SPFI common stock for each share of BOH Holdings, Inc. (&#x201c;BOH&#x201d;) common stock, par value $1.00 per share
(&#x201c;BOH common stock&#x201d;), and (b) an estimate
of the maximum number of shares of BOH
common stock issued and outstanding as of January 28, 2026 or issuable or
expected to be exchanged in connection with the merger of SPFI and BOH,
collectively equal to 2,767,808.&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: left;"&gt;
     &lt;div style="margin-bottom: 4pt;"&gt;
      &lt;span style="font-size: 10.0pt;"&gt;Pursuant to Rules 457(c) and 457(f) promulgated under
the Securities Act and solely for the purpose of calculating the registration
fee, the proposed aggregate maximum offering price is the product of: (A) 14,378,219 (the maximum possible number of shares of BOH
common stock which may be cancelled and exchanged in the merger, and (B) $5.34 (the book value of BOH common stock as of January 28, 2026, the latest practicable date prior to the date of the filing of this
registration statement).&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;(3)&lt;/span&gt;
     &lt;/div&gt;
    &lt;/td&gt;
    &lt;td style="padding: 0px 5.4pt; text-align: left;"&gt;
     &lt;div style="margin-bottom: 4pt;"&gt;
      &lt;span style="font-size: 10.0pt;"&gt;Computed in accordance with Rule 457(f) under the
Securities Act to be $10,603.28, which is equal to 0.00013810 multiplied by the
proposed maximum aggregate offering price of $76,779,689.46.&lt;/span&gt;
     &lt;/div&gt;
    &lt;/td&gt;
   &lt;/tr&gt;
  &lt;/table&gt;</ffd:OfferingNote>
    <ffd:CombinedProspectusTableNa contextRef="c0" id="ixv-264">N/A</ffd:CombinedProspectusTableNa>
    <dei:EntityCentralIndexKey contextRef="c0" id="ixv-265">0001163668</dei:EntityCentralIndexKey>
    <ffd:FeeExhibitTp contextRef="c0" id="ixv-266">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:OffsetTableNa contextRef="c0" id="ixv-267">N/A</ffd:OffsetTableNa>
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