<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>232</ContextCount>
  <ElementCount>343</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>56</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>4</UnitCount>
  <MyReports>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000 - Document - Document And Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-document-and-entity-information</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>001 - Statement - Consolidated Balance Sheets (Current Period Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-balance-sheets-current-period-unaudited</Role>
      <ShortName>Consolidated Balance Sheets (Current Period Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>002 - Statement - Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-balance-sheets-current-period-unaudited-parentheticals</Role>
      <ShortName>Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>003 - Statement - Consolidated Statements of Operations (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-statements-of-operations-unaudited</Role>
      <ShortName>Consolidated Statements of Operations (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>004 - Statement - Consolidated Statements of Comprehensive (Loss) Income (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-statements-of-comprehensive-loss-income-unaudited</Role>
      <ShortName>Consolidated Statements of Comprehensive (Loss) Income (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>005 - Statement - Consolidated Statements of Changes in Stockholders' Equity (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-statements-of-changes-in-stockholders-equity-unaudited</Role>
      <ShortName>Consolidated Statements of Changes in Stockholders' Equity (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>006 - Statement - Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-consolidated-statements-of-cash-flows-unaudited</Role>
      <ShortName>Consolidated Statements of Cash Flows (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>007 - Disclosure - Note 1 - Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-1-basis-of-presentation</Role>
      <ShortName>Note 1 - Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>008 - Disclosure - Note 2 - Use of Estimates and Uncertainties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-2-use-of-estimates-and-uncertainties</Role>
      <ShortName>Note 2 - Use of Estimates and Uncertainties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>009 - Disclosure - Note 3 - Revenue Recognition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition</Role>
      <ShortName>Note 3 - Revenue Recognition</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>010 - Disclosure - Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable</Role>
      <ShortName>Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>011 - Disclosure - Note 5 - Property and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment</Role>
      <ShortName>Note 5 - Property and Equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>012 - Disclosure - Note 6 - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions</Role>
      <ShortName>Note 6 - Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>013 - Disclosure - Note 7 - Goodwill</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-7-goodwill</Role>
      <ShortName>Note 7 - Goodwill</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>014 - Disclosure - Note 8 - Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets</Role>
      <ShortName>Note 8 - Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>015 - Disclosure - Note 9 - Line of Credit</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-9-line-of-credit</Role>
      <ShortName>Note 9 - Line of Credit</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>016 - Disclosure - Note 10 - Per Share Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data</Role>
      <ShortName>Note 10 - Per Share Data</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>017 - Disclosure - Note 11 - Share-based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation</Role>
      <ShortName>Note 11 - Share-based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>018 - Disclosure - Note 12 - Treasury Stock Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-12-treasury-stock-transactions</Role>
      <ShortName>Note 12 - Treasury Stock Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>019 - Disclosure - Note 13 - New Accounting Standards and Updates from the Securities Exchange Commission ("SEC")</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-13-new-accounting-standards-and-updates-from-the-securities-exchange-commission-sec</Role>
      <ShortName>Note 13 - New Accounting Standards and Updates from the Securities Exchange Commission ("SEC")</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>020 - Disclosure - Note 14 - Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-14-segment-information</Role>
      <ShortName>Note 14 - Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>021 - Disclosure - Note 15 - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-15-income-taxes</Role>
      <ShortName>Note 15 - Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>022 - Disclosure - Note 16 - Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-16-contingencies</Role>
      <ShortName>Note 16 - Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>023 - Disclosure - Note 17 - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases</Role>
      <ShortName>Note 17 - Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>024 - Disclosure - Note 18 - Stockholder Rights Plan</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-18-stockholder-rights-plan</Role>
      <ShortName>Note 18 - Stockholder Rights Plan</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>025 - Disclosure - Note 19 - COVID-19</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-19-covid19</Role>
      <ShortName>Note 19 - COVID-19</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>026 - Disclosure - Note 3 - Revenue Recognition (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition-tables</Role>
      <ShortName>Note 3 - Revenue Recognition (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>027 - Disclosure - Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable-tables</Role>
      <ShortName>Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>028 - Disclosure - Note 5 - Property and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment-tables</Role>
      <ShortName>Note 5 - Property and Equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>029 - Disclosure - Note 6 - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions-tables</Role>
      <ShortName>Note 6 - Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>030 - Disclosure - Note 7 - Goodwill (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-7-goodwill-tables</Role>
      <ShortName>Note 7 - Goodwill (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-7-goodwill</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>031 - Disclosure - Note 8 - Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets-tables</Role>
      <ShortName>Note 8 - Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>032 - Disclosure - Note 10 - Per Share Data (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data-tables</Role>
      <ShortName>Note 10 - Per Share Data (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>033 - Disclosure - Note 11 - Share-based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation-tables</Role>
      <ShortName>Note 11 - Share-based Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>034 - Disclosure - Note 14 - Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-14-segment-information-tables</Role>
      <ShortName>Note 14 - Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-14-segment-information</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>035 - Disclosure - Note 17 - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases-tables</Role>
      <ShortName>Note 17 - Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-17-leases</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>036 - Disclosure - Note 1 - Basis of Presentation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-1-basis-of-presentation-details-textual</Role>
      <ShortName>Note 1 - Basis of Presentation (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-1-basis-of-presentation</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>037 - Disclosure - Note 3 - Revenue Recognition (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition-details-textual</Role>
      <ShortName>Note 3 - Revenue Recognition (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition-tables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>038 - Disclosure - Note 3 - Revenue Recognition - Revenues Disaggregated by Revenue Source (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-3-revenue-recognition-revenues-disaggregated-by-revenue-source-details</Role>
      <ShortName>Note 3 - Revenue Recognition - Revenues Disaggregated by Revenue Source (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>039 - Disclosure - Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable-details-textual</Role>
      <ShortName>Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable-tables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>040 - Disclosure - Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable - Accounts Receivable (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-4-accounts-receivable-transit-accounts-receivable-and-transit-accounts-payable-accounts-receivable-details</Role>
      <ShortName>Note 4 - Accounts Receivable, Transit Accounts Receivable and Transit Accounts Payable - Accounts Receivable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>041 - Disclosure - Note 5 - Property and Equipment (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment-details-textual</Role>
      <ShortName>Note 5 - Property and Equipment (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment-tables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>042 - Disclosure - Note 5 - Property and Equipment - Summary of Property and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-5-property-and-equipment-summary-of-property-and-equipment-details</Role>
      <ShortName>Note 5 - Property and Equipment - Summary of Property and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>043 - Disclosure - Note 6 - Acquisitions (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions-details-textual</Role>
      <ShortName>Note 6 - Acquisitions (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions-tables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>044 - Disclosure - Note 6 - Acquisitions - Maximum Deferred Consideration Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-6-acquisitions-maximum-deferred-consideration-payments-details</Role>
      <ShortName>Note 6 - Acquisitions - Maximum Deferred Consideration Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>045 - Disclosure - Note 7 - Goodwill (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-7-goodwill-details-textual</Role>
      <ShortName>Note 7 - Goodwill (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-7-goodwill-tables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>046 - Disclosure - Note 7 - Goodwill - Changes in Carrying Amount of Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-7-goodwill-changes-in-carrying-amount-of-goodwill-details</Role>
      <ShortName>Note 7 - Goodwill - Changes in Carrying Amount of Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>047 - Disclosure - Note 8 - Intangible Assets (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets-details-textual</Role>
      <ShortName>Note 8 - Intangible Assets (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets-tables</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>048 - Disclosure - Note 8 - Intangible Assets - Intangible Assets by Class (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-8-intangible-assets-intangible-assets-by-class-details</Role>
      <ShortName>Note 8 - Intangible Assets - Intangible Assets by Class (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>049 - Disclosure - Note 9 - Line of Credit (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-9-line-of-credit-details-textual</Role>
      <ShortName>Note 9 - Line of Credit (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-9-line-of-credit</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>050 - Disclosure - Note 10 - Per Share Data (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data-details-textual</Role>
      <ShortName>Note 10 - Per Share Data (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data-tables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>051 - Disclosure - Note 10 - Per Share Data - Weighted Average Number of Common Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data-weighted-average-number-of-common-shares-details</Role>
      <ShortName>Note 10 - Per Share Data - Weighted Average Number of Common Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>052 - Disclosure - Note 10 - Per Share Data - Unissued Shares of Common Stock Were Reserved for the Following Purposes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-10-per-share-data-unissued-shares-of-common-stock-were-reserved-for-the-following-purposes-details</Role>
      <ShortName>Note 10 - Per Share Data - Unissued Shares of Common Stock Were Reserved for the Following Purposes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>053 - Disclosure - Note 11 - Share-based Compensation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation-details-textual</Role>
      <ShortName>Note 11 - Share-based Compensation (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation-tables</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>054 - Disclosure - Note 11 - Share-based Compensation - Restricted Stock Units Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-11-sharebased-compensation-restricted-stock-units-activity-details</Role>
      <ShortName>Note 11 - Share-based Compensation - Restricted Stock Units Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>055 - Disclosure - Note 12 - Treasury Stock Transactions (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-12-treasury-stock-transactions-details-textual</Role>
      <ShortName>Note 12 - Treasury Stock Transactions (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-12-treasury-stock-transactions</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>056 - Disclosure - Note 14 - Segment Information - Results of the Segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-14-segment-information-results-of-the-segments-details</Role>
      <ShortName>Note 14 - Segment Information - Results of the Segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>057 - Disclosure - Note 14 - Segment Information - Revenues by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-14-segment-information-revenues-by-geographic-area-details</Role>
      <ShortName>Note 14 - Segment Information - Revenues by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>058 - Disclosure - Note 14 - Segment Information - Total Assets by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-14-segment-information-total-assets-by-geographic-area-details</Role>
      <ShortName>Note 14 - Segment Information - Total Assets by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>059 - Disclosure - Note 15 - Income Taxes (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-15-income-taxes-details-textual</Role>
      <ShortName>Note 15 - Income Taxes (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-15-income-taxes</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>060 - Disclosure - Note 16 - Contingencies (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-16-contingencies-details-textual</Role>
      <ShortName>Note 16 - Contingencies (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-16-contingencies</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>061 - Disclosure - Note 17 - Leases - Lease Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases-lease-expense-details</Role>
      <ShortName>Note 17 - Leases - Lease Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>062 - Disclosure - Note 17 - Leases - Cash Flow Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases-cash-flow-information-details</Role>
      <ShortName>Note 17 - Leases - Cash Flow Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>063 - Disclosure - Note 17 - Leases - Balance Sheet Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases-balance-sheet-information-details</Role>
      <ShortName>Note 17 - Leases - Balance Sheet Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>064 - Disclosure - Note 17 - Leases - Maturities of Lease Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-17-leases-maturities-of-lease-liabilities-details</Role>
      <ShortName>Note 17 - Leases - Maturities of Lease Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="rcmt-20200627.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>065 - Disclosure - Note 18 - Stockholder Rights Plan (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rcmt.com/20200627/role/statement-note-18-stockholder-rights-plan-details-textual</Role>
      <ShortName>Note 18 - Stockholder Rights Plan (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rcmt.com/20200627/role/statement-note-18-stockholder-rights-plan</ParentRole>
      <Position>66</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>rcmt-20200627.xml</File>
    <File>rcmt-20200627.xsd</File>
    <File>rcmt-20200627_cal.xml</File>
    <File>rcmt-20200627_def.xml</File>
    <File>rcmt-20200627_lab.xml</File>
    <File>rcmt-20200627_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/country/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2019-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/us-gaap/2020-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
