<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.7.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>79</ContextCount>
  <ElementCount>212</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>31</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>4</UnitCount>
  <MyReports>
    <Report instance="cmro-20170131.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.comarco.com/20170131/role/statement-document-and-entity-information</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>001 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-consolidated-balance-sheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>002 - Statement - Consolidated Balance Sheets (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-consolidated-balance-sheets-parentheticals</Role>
      <ShortName>Consolidated Balance Sheets (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>003 - Statement - Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-consolidated-statements-of-operations</Role>
      <ShortName>Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>004 - Statement - Consolidated Statements of Stockholders' Equity (Deficit)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-consolidated-statements-of-stockholders-equity-deficit</Role>
      <ShortName>Consolidated Statements of Stockholders' Equity (Deficit)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>005 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-consolidated-statements-of-cash-flows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>006 - Document - Note 1 - Organization</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-1-organization</Role>
      <ShortName>Note 1 - Organization</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>007 - Disclosure - Note 2 - Current and Future Operations, Liquidity, and Capital Resources</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-2-current-and-future-operations-liquidity-and-capital-resources-</Role>
      <ShortName>Note 2 - Current and Future Operations, Liquidity, and Capital Resources</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>008 - Disclosure - Note 3 - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-3-summary-of-significant-accounting-policies</Role>
      <ShortName>Note 3 - Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>009 - Disclosure - Note 4 - Supplier Concentration</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration</Role>
      <ShortName>Note 4 - Supplier Concentration</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>010 - Disclosure - Note 5 - Property and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-5-property-and-equipment</Role>
      <ShortName>Note 5 - Property and Equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>011 - Disclosure - Note 6 - Accrued Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities</Role>
      <ShortName>Note 6 - Accrued Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>012 - Disclosure - Note 7 - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes</Role>
      <ShortName>Note 7 - Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>013 - Disclosure - Note 8 - Stock Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation</Role>
      <ShortName>Note 8 - Stock Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>014 - Disclosure - Note 9 - Net Income (Loss) Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share</Role>
      <ShortName>Note 9 - Net Income (Loss) Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>015 - Disclosure - Note 10 - Employee Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-10-employee-benefit-plans</Role>
      <ShortName>Note 10 - Employee Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>016 - Disclosure - Note 11 - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-11-commitments-and-contingencies</Role>
      <ShortName>Note 11 - Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>017 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-significant-accounting-policies-policies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-3-summary-of-significant-accounting-policies</ParentRole>
      <Position>18</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>018 - Disclosure - Note 4 - Supplier Concentration (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration-tables</Role>
      <ShortName>Note 4 - Supplier Concentration (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>019 - Disclosure - Note 5 - Property and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-5-property-and-equipment-tables</Role>
      <ShortName>Note 5 - Property and Equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-5-property-and-equipment</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>020 - Disclosure - Note 6 - Accrued Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities-tables</Role>
      <ShortName>Note 6 - Accrued Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>021 - Disclosure - Note 7 - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-tables</Role>
      <ShortName>Note 7 - Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-7-income-taxes</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>022 - Disclosure - Note 8 - Stock Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-tables</Role>
      <ShortName>Note 8 - Stock Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>023 - Disclosure - Note 9 - Net Income (Loss) Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share-tables</Role>
      <ShortName>Note 9 - Net Income (Loss) Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>024 - Disclosure - Note 2 - Current and Future Operations, Liquidity, and Capital Resources (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-2-current-and-future-operations-liquidity-and-capital-resources-details-textual</Role>
      <ShortName>Note 2 - Current and Future Operations, Liquidity, and Capital Resources (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-2-current-and-future-operations-liquidity-and-capital-resources-</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>025 - Disclosure - Note 3 - Summary of Significant Accounting Policies (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-3-summary-of-significant-accounting-policies-details-textual</Role>
      <ShortName>Note 3 - Summary of Significant Accounting Policies (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>026 - Disclosure - Note 4 - Supplier Concentration (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration-details-textual</Role>
      <ShortName>Note 4 - Supplier Concentration (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration-tables</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>027 - Disclosure - Note 4 - Supplier Concentration - Supplier Concentration Risk Accounts Receivable and Payable (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-4-supplier-concentration-supplier-concentration-risk-accounts-receivable-and-payable-details</Role>
      <ShortName>Note 4 - Supplier Concentration - Supplier Concentration Risk Accounts Receivable and Payable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>028 - Disclosure - Note 5 - Property and Equipment (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/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.comarco.com/20170131/role/statement-note-5-property-and-equipment-tables</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>029 - Disclosure - Note 5 - Property and Equipment - Components of Property, Plant and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-5-property-and-equipment-components-of-property-plant-and-equipment-details</Role>
      <ShortName>Note 5 - Property and Equipment - Components of Property, Plant and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>030 - Disclosure - Note 6 - Accrued Liabilities (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities-details-textual</Role>
      <ShortName>Note 6 - Accrued Liabilities (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities-tables</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>031 - Disclosure - Note 6 - Accrued Liabilities - Accrued Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-6-accrued-liabilities-accrued-liabilities-details</Role>
      <ShortName>Note 6 - Accrued Liabilities - Accrued Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>032 - Disclosure - Note 7 - Income Taxes (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-details-textual</Role>
      <ShortName>Note 7 - Income Taxes (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-tables</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>033 - Disclosure - Note 7 - Income Taxes - Income Tax Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-income-tax-expense-details</Role>
      <ShortName>Note 7 - Income Taxes - Income Tax Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>034 - Disclosure - Note 7 - Income Taxes - Effective Income Tax Rate Reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-effective-income-tax-rate-reconciliation-details</Role>
      <ShortName>Note 7 - Income Taxes - Effective Income Tax Rate Reconciliation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>035 - Disclosure - Note 7 - Income Taxes - Deferred Tax Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-deferred-tax-assets-and-liabilities-details</Role>
      <ShortName>Note 7 - Income Taxes - Deferred Tax Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>036 - Disclosure - Note 7 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-7-income-taxes-reconciliation-of-unrecognized-tax-benefits-details</Role>
      <ShortName>Note 7 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>037 - Disclosure - Note 8 - Stock Compensation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-details-textual</Role>
      <ShortName>Note 8 - Stock Compensation (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-tables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>038 - Disclosure - Note 8 - Stock Compensation - Weighted Average Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-weighted-average-assumptions-details</Role>
      <ShortName>Note 8 - Stock Compensation - Weighted Average Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>039 - Disclosure - Note 8 - Stock Compensation - Share-based Compensation Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-sharebased-compensation-expense-details</Role>
      <ShortName>Note 8 - Stock Compensation - Share-based Compensation Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>040 - Disclosure - Note 8 - Stock Compensation - Stock Awards Outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-stock-awards-outstanding-details</Role>
      <ShortName>Note 8 - Stock Compensation - Stock Awards Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>041 - Disclosure - Note 8 - Stock Compensation - Stock Options Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-8-stock-compensation-stock-options-activity-details</Role>
      <ShortName>Note 8 - Stock Compensation - Stock Options Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>042 - Disclosure - Note 9 - Net Income (Loss) Per Share (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share-details-textual</Role>
      <ShortName>Note 9 - Net Income (Loss) Per Share (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share-tables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>043 - Disclosure - Note 9 - Net Income (Loss) Per Share - Summary of Basic and Diluted Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share-summary-of-basic-and-diluted-earnings-per-share-details</Role>
      <ShortName>Note 9 - Net Income (Loss) Per Share - Summary of Basic and Diluted Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-9-net-income-loss-per-share-tables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>044 - Disclosure - Note 10 - Employee Benefit Plans (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-10-employee-benefit-plans-details-textual</Role>
      <ShortName>Note 10 - Employee Benefit Plans (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-10-employee-benefit-plans</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="cmro-20170131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>045 - Disclosure - Note 11 - Commitments and Contingencies (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.comarco.com/20170131/role/statement-note-11-commitments-and-contingencies-details-textual</Role>
      <ShortName>Note 11 - Commitments and Contingencies (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.comarco.com/20170131/role/statement-note-11-commitments-and-contingencies</ParentRole>
      <Position>46</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>cmro-20170131.xml</File>
    <File>cmro-20170131.xsd</File>
    <File>cmro-20170131_cal.xml</File>
    <File>cmro-20170131_def.xml</File>
    <File>cmro-20170131_lab.xml</File>
    <File>cmro-20170131_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies/>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
