<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2026"
  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"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <link:schemaRef
      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
      xlink:type="simple"/>
    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000775215</identifier>
        </entity>
        <period>
            <startDate>2026-08-31</startDate>
            <endDate>2026-08-31</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000775215</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
                </xbrldi:typedMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-31</startDate>
            <endDate>2026-08-31</endDate>
        </period>
    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-330">S-4</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-331">S-4</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-332">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-333">0000775215</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-334">HBT Financial, Inc.</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
    <ffd:CombinedProspectusTableNa contextRef="rc" id="hiddenrcCombinedProspectusTableNa">N/A</ffd:CombinedProspectusTableNa>
    <ffd:FormTp contextRef="rc" id="ixv-362">S-4</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-363">HBT Financial, Inc.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-364">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-365">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-366">Common Stock, par value $0.01 per share</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="offrl_1" id="ixv-367">true</ffd:FeesOthrRuleFlg>
    <ffd:AmtSctiesRegd
      contextRef="offrl_1"
      decimals="0"
      id="ixv-368"
      unitRef="Shares">3797845</ffd:AmtSctiesRegd>
    <ffd:MaxAggtOfferingPric
      contextRef="offrl_1"
      decimals="2"
      id="ixv-369"
      unitRef="USD">140591883.00</ffd:MaxAggtOfferingPric>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-370"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-371"
      unitRef="USD">19415.74</ffd:FeeAmt>
    <ffd:TtlOfferingAmt contextRef="rc" decimals="2" id="ixv-372" unitRef="USD">140591883.00</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-373" unitRef="USD">19415.74</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-374" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-375" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-376" unitRef="USD">19415.74</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-377">Rule 457(f) Fee Calculation Details

The amount in the "Amount Registered" column represents the estimated maximum number of shares of HBT Financial, Inc. ("HBT") common stock to be issued upon completion of HBT's acquisition of Tri-County Financial Group, Inc. ("TYFG") as described in the proxy statement/prospectus contained in the registration statement to which this Exhibit 107 is attached. The amount in the "Maximum Aggregate Offering Price" column is estimated solely for the purpose of calculating the registration fee and has been calculated in accordance with Rule 457(f)(1) and (3) of the Securities Act of 1933 (as amended, the "Securities Act") as follows: the product of (A) $79.40, the last sale price per share of TYFG's common stock as reported on the OTCQX on August 28, 2026, and (B) 2,525,683, the estimated maximum number of shares of TYFG common stock to be exchanged in the merger, including shares reserved for issuance pursuant to outstanding stock options, minus $59,947,348, the estimated aggregate amount of cash that is to be payable in respect of such shares in connection with the merger. Pursuant to Rule 457(o) of the Securities Act, the registration fee, reflected in the "Amount of Registration Fee" column, has been calculated on the basis of the maximum aggregate offering price. The fee has been calculated in accordance with Section 6(b) of the Securities Act by multiplying the proposed maximum aggregate offering price of securities to be registered as calculated pursuant to Rule 457(f)(1) and (3) of the Securities Act by 0.00013810
</ffd:OfferingNote>
</xbrl>
