<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.8.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>150</ContextCount>
  <ElementCount>254</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>60</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>4</UnitCount>
  <MyReports>
    <Report instance="cabo-20180331.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.cableone.net/20180331/role/statement-document-and-entity-information</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>001 - Statement - Condensed Consolidated Balance Sheets (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-condensed-consolidated-balance-sheets-unaudited</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>002 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-condensed-consolidated-balance-sheets-unaudited-parentheticals</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>003 - Statement - Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-condensed-consolidated-statements-of-operations-and-comprehensive-income-unaudited</Role>
      <ShortName>Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>004 - Statement - Condensed Consolidated Statement of Stockholders' Equity (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-condensed-consolidated-statement-of-stockholders-equity-unaudited</Role>
      <ShortName>Condensed Consolidated Statement of Stockholders' Equity (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>005 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-condensed-consolidated-statements-of-cash-flows-unaudited</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>006 - Disclosure - Note 1 - Description of Business and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-1-description-of-business-and-basis-of-presentation</Role>
      <ShortName>Note 1 - Description of Business and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>007 - Disclosure - Note 2 - Revision of Previously Issued Financial Statements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-2-revision-of-previously-issued-financial-statements</Role>
      <ShortName>Note 2 - Revision of Previously Issued Financial Statements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>008 - Disclosure - Note 3 - Adoption of New Revenue Recognition Standard</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-3-adoption-of-new-revenue-recognition-standard</Role>
      <ShortName>Note 3 - Adoption of New Revenue Recognition Standard</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>009 - Disclosure - Note 4 - NewWave Acquisition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-4-newwave-acquisition</Role>
      <ShortName>Note 4 - NewWave Acquisition</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>010 - Disclosure - Note 5 - Revenues</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-5-revenues-</Role>
      <ShortName>Note 5 - Revenues</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>011 - Disclosure - Note 6 - Property, Plant and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-6-property-plant-and-equipment</Role>
      <ShortName>Note 6 - Property, Plant and Equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>012 - Disclosure - Note 7 - Goodwill and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-7-goodwill-and-intangible-assets</Role>
      <ShortName>Note 7 - Goodwill and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>013 - Disclosure - Note 8 - Long-term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-8-longterm-debt</Role>
      <ShortName>Note 8 - Long-term Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>014 - Disclosure - Note 9 - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-9-fair-value-measurements</Role>
      <ShortName>Note 9 - Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>015 - Disclosure - Note 10 - Treasury Stock</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-10-treasury-stock</Role>
      <ShortName>Note 10 - Treasury Stock</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>016 - Disclosure - Note 11 - Equity-based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation</Role>
      <ShortName>Note 11 - Equity-based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>017 - Disclosure - Note 12 - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-12-income-taxes-</Role>
      <ShortName>Note 12 - Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>018 - Disclosure - Note 13 - Net Income Per Common Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-13-net-income-per-common-share</Role>
      <ShortName>Note 13 - Net Income Per Common Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>019 - Document - Note 14 - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-14-commitments-and-contingencies</Role>
      <ShortName>Note 14 - Commitments and Contingencies</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>020 - Disclosure - Note 15 - Subsequent Event</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-15-subsequent-event</Role>
      <ShortName>Note 15 - Subsequent Event</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>021 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-significant-accounting-policies-policies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>022 - Disclosure - Note 2 - Revision of Previously Issued Financial Statements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-2-revision-of-previously-issued-financial-statements-tables</Role>
      <ShortName>Note 2 - Revision of Previously Issued Financial Statements (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>023 - Disclosure - Note 3 - Adoption of New Revenue Recognition Standard (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-3-adoption-of-new-revenue-recognition-standard-tables</Role>
      <ShortName>Note 3 - Adoption of New Revenue Recognition Standard (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>024 - Disclosure - Note 4 - NewWave Acquisition (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-4-newwave-acquisition-tables</Role>
      <ShortName>Note 4 - NewWave Acquisition (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>025 - Disclosure - Note 5 - Revenues (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-5-revenues-tables</Role>
      <ShortName>Note 5 - Revenues (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>026 - Disclosure - Note 6 - Property, Plant and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-6-property-plant-and-equipment-tables</Role>
      <ShortName>Note 6 - Property, Plant and Equipment (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>027 - Disclosure - Note 7 - Goodwill and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-7-goodwill-and-intangible-assets-tables</Role>
      <ShortName>Note 7 - Goodwill and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>028 - Disclosure - Note 8 - Long-term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-8-longterm-debt-tables</Role>
      <ShortName>Note 8 - Long-term Debt (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>029 - Disclosure - Note 9 - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-9-fair-value-measurements-tables</Role>
      <ShortName>Note 9 - Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>030 - Disclosure - Note 11 - Equity-based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation-tables</Role>
      <ShortName>Note 11 - Equity-based Compensation (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>031 - Disclosure - Note 13 - Net Income Per Common Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-13-net-income-per-common-share-tables</Role>
      <ShortName>Note 13 - Net Income Per Common Share (Tables)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>032 - Disclosure - Note 1 - Description of Business and Basis of Presentation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-1-description-of-business-and-basis-of-presentation-details-textual</Role>
      <ShortName>Note 1 - Description of Business and Basis of Presentation (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>033 - Disclosure - Note 2 - Revision of Previously Issued Financial Statements (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-2-revision-of-previously-issued-financial-statements-details-textual</Role>
      <ShortName>Note 2 - Revision of Previously Issued Financial Statements (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>034 - Disclosure - Note 2 - Revision of Previously Issued Financial Statements - Revisions on Consolidated Financial Statements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-2-revision-of-previously-issued-financial-statements-revisions-on-consolidated-financial-statements-details</Role>
      <ShortName>Note 2 - Revision of Previously Issued Financial Statements - Revisions on Consolidated Financial Statements (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>035 - Disclosure - Note 3 - Adoption of New Revenue Recognition Standard - Impact of ASC 606 Adoption (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-3-adoption-of-new-revenue-recognition-standard-impact-of-asc-606-adoption-details</Role>
      <ShortName>Note 3 - Adoption of New Revenue Recognition Standard - Impact of ASC 606 Adoption (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>036 - Disclosure - Note 4 - NewWave Acquisition (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-4-newwave-acquisition-details-textual</Role>
      <ShortName>Note 4 - NewWave Acquisition (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>037 - Disclosure - Note 4 - NewWave Acquisition - Allocation of Purchase Price Consideration (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-4-newwave-acquisition-allocation-of-purchase-price-consideration-details</Role>
      <ShortName>Note 4 - NewWave Acquisition - Allocation of Purchase Price Consideration (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>038 - Disclosure - Note 5 - Revenues (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-5-revenues-details-textual</Role>
      <ShortName>Note 5 - Revenues (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>039 - Disclosure - Note 5 - Revenues - Revenues by Product Line (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-5-revenues-revenues-by-product-line-details</Role>
      <ShortName>Note 5 - Revenues - Revenues by Product Line (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>040 - Disclosure - Note 6 - Property, Plant and Equipment (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-6-property-plant-and-equipment-details-textual</Role>
      <ShortName>Note 6 - Property, Plant and Equipment (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>041 - Disclosure - Note 6 - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-6-property-plant-and-equipment-schedule-of-property-plant-and-equipment-details</Role>
      <ShortName>Note 6 - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>042 - Disclosure - Note 7 - Goodwill and Intangible Assets (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-7-goodwill-and-intangible-assets-details-textual</Role>
      <ShortName>Note 7 - Goodwill and Intangible Assets (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>043 - Disclosure - Note 7 - Goodwill and Intangible Assets - Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-7-goodwill-and-intangible-assets-intangible-assets-details</Role>
      <ShortName>Note 7 - Goodwill and Intangible Assets - Intangible Assets (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>044 - Disclosure - Note 7 - Goodwill and Intangible Assets - Amortization of Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-7-goodwill-and-intangible-assets-amortization-of-intangible-assets-details</Role>
      <ShortName>Note 7 - Goodwill and Intangible Assets - Amortization of Intangible Assets (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>045 - Disclosure - Note 8 - Long-term Debt (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-8-longterm-debt-details-textual</Role>
      <ShortName>Note 8 - Long-term Debt (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>046 - Disclosure - Note 8 - Long-term Debt - Schedule of Long-term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-8-longterm-debt-schedule-of-longterm-debt-details</Role>
      <ShortName>Note 8 - Long-term Debt - Schedule of Long-term Debt (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>047 - Disclosure - Note 8 - Long-term Debt - Future Maturities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-8-longterm-debt-future-maturities-details</Role>
      <ShortName>Note 8 - Long-term Debt - Future Maturities (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>048 - Disclosure - Note 9 - Fair Value Measurements (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-9-fair-value-measurements-details-textual</Role>
      <ShortName>Note 9 - Fair Value Measurements (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>049 - Disclosure - Note 9 - Fair Value Measurements - Carrying Amounts and Fair Values (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-9-fair-value-measurements-carrying-amounts-and-fair-values-details</Role>
      <ShortName>Note 9 - Fair Value Measurements - Carrying Amounts and Fair Values (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>050 - Disclosure - Note 10 - Treasury Stock (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-10-treasury-stock-details-textual</Role>
      <ShortName>Note 10 - Treasury Stock (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>051 - Disclosure - Note 11 - Equity-based Compensation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation-details-textual</Role>
      <ShortName>Note 11 - Equity-based Compensation (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>052 - Disclosure - Note 11 - Equity-based Compensation - Restricted Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation-restricted-stock-details</Role>
      <ShortName>Note 11 - Equity-based Compensation - Restricted Stock (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>053 - Disclosure - Note 11 - Equity-based Compensation - Stock Appreciation Rights (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation-stock-appreciation-rights-details</Role>
      <ShortName>Note 11 - Equity-based Compensation - Stock Appreciation Rights (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>054 - Disclosure - Note 11 - Equity-based Compensation - Stock Appreciation Rights, Fair Value Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-11-equitybased-compensation-stock-appreciation-rights-fair-value-assumptions-details</Role>
      <ShortName>Note 11 - Equity-based Compensation - Stock Appreciation Rights, Fair Value Assumptions (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>055 - Disclosure - Note 12 - Income Taxes (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-12-income-taxes-details-textual</Role>
      <ShortName>Note 12 - Income Taxes (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>056 - Disclosure - Note 13 - Net Income Per Common Share (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-13-net-income-per-common-share-details-textual</Role>
      <ShortName>Note 13 - Net Income Per Common Share (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>057 - Disclosure - Note 13 - Net Income Per Common Share - Computation of Basic and Diluted Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-13-net-income-per-common-share-computation-of-basic-and-diluted-earnings-per-share-details</Role>
      <ShortName>Note 13 - Net Income Per Common Share - Computation of Basic and Diluted Earnings Per Share (Details)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="cabo-20180331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>058 - Disclosure - Note 15 - Subsequent Event (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cableone.net/20180331/role/statement-note-15-subsequent-event-details-textual</Role>
      <ShortName>Note 15 - Subsequent Event (Details Textual)</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>cabo-20180331.xml</File>
    <File>cabo-20180331.xsd</File>
    <File>cabo-20180331_cal.xml</File>
    <File>cabo-20180331_def.xml</File>
    <File>cabo-20180331_lab.xml</File>
    <File>cabo-20180331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/us-gaap/2018-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2014-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2018-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
