Document And Entity Information Note To Financial Statement Details Textual us-gaap_InterestExpense Interest expense Property, Plant and Equipment Disclosure [Text Block] us-gaap_AmortizationOfFinancingCosts Amortization of Debt Issuance Costs statementsignificantaccountingpoliciespolicies statementnote2summaryofsignificantaccountingpoliciestables Property, Plant and Equipment [Table Text Block] statementnote3revenuestables us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable Income taxes payable statementnote4accountsreceivableaccountspayableandaccruedliabilitiestables us-gaap_DefinedBenefitPlanActuarialGainLoss Actuarial loss (gain) statementnote5propertyplantandequipmenttables statementnote6goodwillandintangibleassetstables statementnote7longtermdebttables Consolidation, Policy [Policy Text Block] statementnote8incometaxestables statementnote9fairvaluemeasurementstables statementnote11equitybasedcompensationtables statementnote14definedbenefitpostretirementplantables statementnote15netincomepersharetables us-gaap_IncreaseDecreaseInDeferredRevenue Deferred revenue statementnote16relatedpartytransactionstables statementnote17commitmentsandcontingenciestables statementnote18summaryofquarterlyoperatingresultstables statementnote2summaryofsignificantaccountingpoliciespropertyplantandequipmentusefullivesdetails us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities Accounts payable and accrued liabilities statementnote3revenuesrevenuesbyproductlinedetails statementnote4accountsreceivableaccountspayableandaccruedliabilitiessummaryofaccountsreceivabledetails statementnote4accountsreceivableaccountspayableandaccruedliabilitiesallowancefordoubtfulaccountsdetails Reclassification of Additional GHC investment (deficit) in connection with spin-off The amount reclassified in additional parent company investment (deficit) in connection with the spin-off. statementnote4accountsreceivableaccountspayableandaccruedliabilitiesaccountspayableandaccruedliabilitiesdetails statementnote5propertyplantandequipmentscheduleofpropertyplantandequipmentdetails statementnote6goodwillandintangibleassetsintangibleassetsdetails cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageGrantDateFairValue Outstanding, Beginning Balance, weighted average fair value (in dollars per share) Outstanding, Beginning Balance, weighted average fair value (in dollars per share) The weighted average fair value of outstanding awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. statementnote7longtermdebtscheduleoflongtermdebtdetails Restricted Stock and Restricted Stock Units [Member] Stock including a provision that prohibits sale or substantive sale of an equity instrument and share instruments which are convertible to stock or an equivalent amount of cash for a specified period of time or until specified performance conditions are met. statementnote7longtermdebtfuturematuritiesdetails statementnote8incometaxesprovisionforincometaxesdetails statementnote8incometaxesincometaxratereconciliationdetails statementnote8incometaxesdeferredincometaxesdetails statementnote9fairvaluemeasurementscarryingamountsandfairvaluesdetails statementnote11equitybasedcompensationsummaryofrestrictedstockdetails statementnote11equitybasedcompensationsummaryofstockappreciationrightsdetails statementnote11equitybasedcompensationstockappreciationrightsfairvalueassumptionsdetails statementnote14definedbenefitpostretirementplanassetandfundinginformationdetails us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo Finite-Lived Intangible Assets, Amortization Expense, Year Two statementnote14definedbenefitpostretirementplanamountsrecognizedinbalancesheetdetails us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree Finite-Lived Intangible Assets, Amortization Expense, Year Three statementnote14definedbenefitpostretirementplanfutureestimatedbenefitpaymentsdetails statementnote14definedbenefitpostretirementplanamortizationcomponentsofnetperiodicdetails us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months statementnote15netincomepersharecomputationofbasicanddilutedearningspersharedetails statementnote16relatedpartytransactionscomponentsofnettransferstoparentdetails statementnote17commitmentsandcontingenciescontractualobligationmaturitydetails statementnote18summaryofquarterlyoperatingresultsquarterlyfinancialdatadetails Notes To Financial Statements Notes To Financial Statements [Abstract] Useful Life (Year) us-gaap_ComprehensiveIncomeNetOfTax Comprehensive income us-gaap_TreasuryStockSharesAcquired Treasury Stock, Shares, Acquired Repurchase of common stock (in shares) Repurchase of common stock (in shares) us-gaap_PreferredStockSharesOutstanding Preferred Stock, Shares Outstanding Common stock, shares outstanding (in shares) Cash and cash equivalents us-gaap_CashAndCashEquivalentsAtCarryingValue Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Postemployment Benefits Disclosure [Text Block] us-gaap_AllocatedShareBasedCompensationExpense Allocated Share-based Compensation Expense us-gaap_DeferredTaxAssetsNet Deferred Tax Assets Excess income tax benefits for equity-based compensation activities us-gaap_DeferredIncomeTaxLiabilities Deferred Tax Liabilities us-gaap_IncreaseDecreaseInPrepaidExpense Prepaid assets us-gaap_DeferredTaxAssetsOther Other Equity-based compensation Equity-based compensation us-gaap_LettersOfCreditOutstandingAmount Letters of Credit Outstanding, Amount us-gaap_TreasuryStockValueAcquiredCostMethod Treasury Stock, Value, Acquired, Cost Method Repurchase of common stock Repurchase of common stock us-gaap_TreasuryStockValue Treasury stock, at cost (179,676 and 46,483 shares held as of December 31, 2016 and 2015, respectively) Revenues Revenues us-gaap_IncreaseDecreaseInAccountsReceivable Accounts receivable, net us-gaap_SalesRevenueServicesNet Revenues us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts Accounts receivable us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsOther Other benefit obligations us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost us-gaap_OtherSalesRevenueNet Other Fair Value of Financial Instruments, Policy [Policy Text Block] Issuance of restricted stock awards, net of forfeitures (in shares) Fair Value Measurement, Policy [Policy Text Block] us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited Forfeiture of restricted stock (in shares) Segment Reporting, Policy [Policy Text Block] Fair Value Disclosures [Text Block] Self Insurance Reserve [Policy Text Block] us-gaap_AllowanceForDoubtfulAccountsReceivable Balance at beginning of period Balance at end of period Issuance of common stock under restricted stock unit awards (in shares) us-gaap_AdvertisingRevenue Advertising sales Equity-based compensation (in shares) Equity-based compensation (in shares) Base Rate [Member] Issuance of common stock under restricted stock unit awards Postemployment Benefit Plans, Pre-Spin [Member] Information pertaining to the pre-spin of the postemployment benefit plans. Postemployment Benefit Plans, Post-Spin [Member] Information pertaining to the post-spin of the postemployment benefit plans. Income Tax, Policy [Policy Text Block] us-gaap_DeferredTaxLiabilities Deferred Income Tax Liabilities us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets Goodwill and other intangible assets us-gaap_LiabilitiesAndStockholdersEquity Total Liabilities and Stockholders' Equity Defined Contribution Supplemental Executive Retirement Plan [Member] Information pertaining to the Defined Contribution Supplemental Executive Retirement Plan (DC SERP). cabo_PaymentOfDividendsToParent Dividends paid to GHC Cash outflow in the form of capital distributions and dividends to the parent company. Retained earnings Accumulated other comprehensive loss Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Chief Executive Officer [Member] Utility Pole [Member] Represents utility poles. Programming Costs, Policy [Policy Text Block] Disclosure of accounting policy for programming costs. Property, Plant and Equipment Useful Lives [Table Text Block] Tabular disclosure of the useful lives of physical assets used in the normal conduct of business. Pension and Other Postretirement Plans, Policy [Policy Text Block] cabo_ContractualObligationFranchiseAgreementsNonperformance Contractual Obligation, Franchise Agreements, Nonperformance Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, which payments are required only in the event of nonperformance under franchise agreements. us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment Property, plant and equipment Advertising Costs, Policy [Policy Text Block] Accounts Receivable, Accounts Payable and Accrued Liabilities Disclosure [Text Block] The entire disclosure for accounts receivable, accounts payable and accrued liabilities at the end of the reporting period. us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased Stock Repurchase Program, Number of Shares Authorized to be Repurchased Accrued Compensation and Related Benefits [Member] Primary financial statement caption encompassing accrued compensation and related benefits. Schedule of Allowance for Doubtful Accounts [Table Text Block] Tabular disclosure for allowance for doubtful accounts (their beginning and ending balances, as well as a reconciliation by type of activity during the period). us-gaap_StockRepurchaseProgramAuthorizedAmount1 Stock Repurchase Program, Authorized Amount cabo_ProgrammingCostsCurrent Programming costs Carrying value as of the balance sheet date of programming costs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). cabo_FranchiseFeesCurrent Franchise fees Carrying value as of the balance sheet date of franchise fees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). State and Local Current State and Local Changes in operating assets and liabilities: Deferred State and Local Wireless Spectrum Licenses [Member] Information pertaining to wireless spectrum licenses. U.S. Federal us-gaap_AssetsFairValueDisclosure Assets Current U.S. Federal Deferred U.S. Federal Current Income Taxes Deferred Income Taxes Deferred income taxes Asset Class [Domain] Asset Class [Axis] 401 (k) Plan [Member] Represents 401 (k) Savings Plan us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities Excess income tax benefits for equity-based compensation activities us-gaap_ShareBasedCompensation Equity-based compensation Other assets us-gaap_PensionExpense Pension Expense Treasury stock, shares (in shares) Treasury Stock, Shares Revenue Recognition, Policy [Policy Text Block] Common stock ($0.01 par value; 40,000,000 shares authorized; 5,887,899 and 5,879,925 shares issued, and 5,708,223 and 5,833,442 shares outstanding as of December 31, 2016 and 2015, respectively) us-gaap_TableTextBlock Notes Tables cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVestedAndDeferredNumber Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested and Deferred, Number Number of equity instruments other than options that are vested and deferred as of the balance sheet date. Common stock, shares issued (in shares) Common Stock, Shares, Issued Non-employee Directors [Member Represents information pertaining to non-employee directors. Common stock, shares authorized (in shares) Asset Retirement Obligations, Policy [Policy Text Block] Commercial Paper [Member] Amendment Flag us-gaap_DepreciationDepletionAndAmortization Depreciation and amortization Common stock, par value (in dollars per share) us-gaap_Depreciation Depreciation us-gaap_AssetsCurrent Total Current Assets Other income (expense), net Goodwill and Intangible Assets, Policy [Policy Text Block] Spinoff [Member] Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Type of Restructuring [Domain] Current Fiscal Year End Date Restructuring Type [Axis] us-gaap_ContractualObligationDueAfterFifthYear Thereafter us-gaap_PreferredStockSharesIssued Preferred Stock, Shares Issued us-gaap_ContractualObligation Total Adjustments to reconcile net income to net cash provided by operating activities: us-gaap_ContractualObligationDueInFifthYear 2021 Statement of Financial Position [Abstract] Document Fiscal Period Focus Document Fiscal Year Focus us-gaap_ContractualObligationDueInFourthYear 2020 us-gaap_ContractualObligationDueInThirdYear 2019 Document Period End Date us-gaap_ContractualObligationDueInSecondYear 2018 us-gaap_ContractualObligationDueInNextTwelveMonths 2017 us-gaap_PurchaseObligation Total Document Type Statement of Cash Flows [Abstract] us-gaap_OperatingIncomeLoss Income from operations Income from operations us-gaap_PurchaseObligationDueAfterFifthYear Thereafter us-gaap_PurchaseObligationDueInFourthYear 2020 Long-term Debt [Member] us-gaap_PurchaseObligationDueInFifthYear 2021 Statement of Stockholders' Equity [Abstract] Document Information [Line Items] Document Information [Table] us-gaap_PurchaseObligationDueInSecondYear 2018 us-gaap_InterestPaid Cash paid for interest expense us-gaap_PurchaseObligationDueInThirdYear 2019 us-gaap_IncomeTaxesPaid Cash paid for income taxes Entity Public Float us-gaap_PurchaseObligationDueInNextTwelveMonths 2017 Entity Filer Category Property, Plant and Equipment Useful Lives (Year) Entity Current Reporting Status Other Capitalized Property Plant and Equipment [Member] us-gaap_OperatingLeasesFutureMinimumPaymentsDue Total Entity Voluntary Filers Software and Software Development Costs [Member] Entity Well-known Seasoned Issuer us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter Thereafter us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears 2020 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears 2021 Construction in Progress [Member] Prepaid assets us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears 2018 us-gaap_FranchiseCosts Franchise Costs us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears 2019 Furniture and Fixtures [Member] us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent 2017 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive Thereafter cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedWeightedAverageRemainingContractualTerm Weighted Average Remaining Contractual Term, Granted (Year) Weighted average remaining contractual term for equity-based awards excluding options granted during the period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour 2020 Building and Building Improvements [Member] 2021 2021 Entity Central Index Key us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo 2018 Entity Registrant Name us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree 2019 Building [Member] Entity [Domain] us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths 2017 Business Acquisition, Acquiree [Domain] Legal Entity [Axis] Business Acquisition [Axis] Land [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Additional paid-in capital Stockholders' Equity Entity Common Stock, Shares Outstanding (in shares) Cash flows from operating activities: us-gaap_OtherCommitment Total Statement [Line Items] us-gaap_OtherCommitmentDueAfterFifthYear Thereafter us-gaap_OtherCommitmentDueInFourthYear 2020 us-gaap_OtherCommitmentDueInFifthYear 2021 Accounts receivable, net Total accounts receivable, net us-gaap_OtherCommitmentDueInSecondYear 2018 us-gaap_OtherCommitmentDueInThirdYear 2019 us-gaap_OtherCommitmentDueInNextTwelveMonths 2017 Trading Symbol AOCI Attributable to Parent [Member] us-gaap_AccountsReceivableNetCurrent Accounts receivable, net us-gaap_Liabilities Total Liabilities Commitments and contingencies (see Note 17) Other comprehensive gain (loss), net of tax Changes in pension, net of tax us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent Recognized Asset (Liability) Current Assets: us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities Current liability us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent Noncurrent liability us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease Change in cash and cash equivalents us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent Deferred Compensation Liability, Current and Noncurrent Concentration Risk, Credit Risk, Policy [Policy Text Block] us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations Net cash (used in) provided by financing activities us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations Net cash provided by operating activities us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations Net cash used in investing activities Subscriber deposits Carrying value as of the balance sheet date of obligations incurred through that date and payable in relation to subscriber deposits. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Type of Adoption [Domain] us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities Excess income tax benefits for equity-based compensation activities us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation Payments Related to Tax Withholding for Share-based Compensation Payment of withholding tax for restricted shares Adjustments for New Accounting Pronouncements [Axis] us-gaap_PaymentsOfDividends Dividends paid to stockholders us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Other, net us-gaap_PaymentsForRepurchaseOfCommonStock Repurchase of common stock us-gaap_StockholdersEquity Total Stockholders' Equity Balance Balance Retained Earnings [Member] Treasury Stock [Member] Additional Paid-in Capital [Member] us-gaap_CostsAndExpenses Total operating costs and expenses Common Stock [Member] Equity Components [Axis] Equity Component [Domain] Report Date [Axis] Financial Statement Filing Date [Domain] Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Capital lease obligation Risk-free interest rate Total Long-term debt, including current portion Long-term Debt Total Expected volatility Other Assets [Member] us-gaap_BusinessCombinationConsiderationTransferred1 Business Combination, Consideration Transferred Expected term (in years) (Year) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms Weighted Average Remaining Contractual Term, Outstanding (Year) us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding Outstanding, aggregate intrinsic value cabo_PaymentsToAcquirePropertyPlantAndEquipmentIncludingChangesInAccruedExpensesRelatedToCapitalExpenditures Payments to Acquire Property, Plant, and Equipment, Including Changes in Accrued Expenses Related to Capital Expenditures The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets including cash outflow from changes in accrued expenses related to capital expenditures. us-gaap_PaymentsOfDebtIssuanceCosts Payments of debt issue costs U.S. Federal taxes at statutory rate Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy [Policy Text Block] State and local taxes, net of U.S. Federal tax us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue Forfeited, restricted stock, weighted average grant date fair value (in dollars per share) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue Unvested, restricted stock, weighted avergae grant date fair value (in dollars per share) Unvested, restricted stock, weighted avergae grant date fair value (in dollars per share) Cash and Cash Equivalents, Policy [Policy Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue Granted, restricted stock, weighted avergae grant date fair value (in dollars per share) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue Vested, restricted stock, weighted avergae grant date fair value (in dollars per share) Significant Accounting Policies [Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber Unvested, restricted stock (in shares) Unvested, restricted stock (in shares) Basis of Accounting, Policy [Policy Text Block] Income Tax Disclosure [Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod Forfeited, restricted stock (in shares) us-gaap_DeferredFinanceCostsNet Less unamortized debt issuance costs Accounting Policies [Abstract] us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest Income before income taxes us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod Granted, restricted stock (in shares) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod Vested, restricted stock (in shares) Equipment [Member] us-gaap_RepaymentsOfLongTermDebt Payments on long-term debt Balance Sheet Location [Domain] Balance Sheet Location [Axis] Selling, General and Administrative Expenses [Member] Other Nonoperating Income (Expense) [Member] Revolving Credit Facility [Member] us-gaap_OtherReceivablesNetCurrent Other receivables us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs Deductions Credit Facility [Domain] Secured Debt [Member] Credit Facility [Axis] us-gaap_BankOverdrafts Cash overdrafts Long-term debt Total long-term debt us-gaap_ProceedsFromIssuanceOfLongTermDebt Proceeds from issuance of long-term debt, net of issuance costs Total debt us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number Outstanding, stock appreciation rights (in shares) Outstanding, stock appreciation rights (in shares) Income Statement Location [Domain] Income Statement Location [Axis] Maximum [Member] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures Minimum [Member] Range [Axis] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Range [Domain] Franchise Rights [Member] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets [Axis] Use Rights [Member] Goodwill and Intangible Assets Disclosure [Text Block] us-gaap_OperatingLeasesRentExpenseNet Operating Leases, Rent Expense, Net us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAcceleratedVestingNumber Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number Treasury Stock [Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized us-gaap_EquityMethodInvestmentOwnershipPercentage Equity Method Investment, Ownership Percentage us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Products and Services [Domain] Products and Services [Axis] Plan Name [Axis] Plan Name [Domain] us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount us-gaap_ProceedsFromRepaymentsOfBankOverdrafts Cash overdraft us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding Diluted (in shares) Weighted average common shares outstanding - Diluted (in shares) us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1 Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition cabo_ConversionOfHoldingCompanyStockToNewReportingEntityOutstandingNumber Conversion of Holding Company Stock to new Reporting Entity, Outstanding Number Represents the total number of outstanding shares of the holding company that were converted into the new reporting entity in the spinoff. us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options Graham Holding Company [Member] Represents the Graham holding company. Award Type [Axis] Equity Award [Domain] Senior Unsecured Notes Due 2022 [Member] Represents the senior unsecured notes due 2022. us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Finite-Lived Intangible Assets by Major Class [Axis] us-gaap_EarningsPerShareDiluted Diluted (in dollars per share) Finite-Lived Intangible Assets, Major Class Name [Domain] Scenario, Forecast [Member] cabo_PercentageOfAggregatePrincipalAmountForDebtRedemptionPriorToRepurchasePremiumCutoffDate Percentage of Aggregate Principal Amount for Debt Redemption Prior to Repurchase Premium Cutoff Date Represents the percentage of the aggregate principal amount to be paid for the debt redemption prior to the redemption premium cutoff date. Scenario, Unspecified [Domain] us-gaap_WeightedAverageNumberOfSharesOutstandingBasic Basic (in shares) cabo_DebtInstrumentMaximumPercentageOfRedemptionPriorToPremiumCutoffDateAllowableWithoutRedemptionPremium Debt Instrument, Maximum Percentage of Redemption Prior to Premium Cutoff Date, Allowable Without Redemption Premium Represents the maximum percentage of notes payable to be redeemed prior to the redemption premium cutoff date that is allowable with out the debt redemption premium being paid. Scenario [Axis] cabo_MinimumPercentageOfDebtToBeHeldInOrderToDeclareNotesPayableImmediatelyInEventOfDefault Minimum Percentage of Debt to be held in Order to Declare Notes Payable Immediately in Event of Default Represents the minimum percentage of debt to be held if the holder wishes to declare the notes payable immediately in case of default. cabo_PercentageOfAggregatePrincipalAmountForDebtRedemptionPriorToThePremiumCutoffDateToBePurchasedWithoutRepdemptionPremium Percentage of Aggregate Principal Amount for Debt Redemption Prior to the Premium Cutoff Date to be Purchased Without Repdemption Premium Represents the percentage of the aggregate principal amount that must be paid to redeem the debt prior to the redemption premium cutoff date if the percentage of debt repurchased is less than the amount necessary to trigger the redemption premium. Disclosure of Compensation Related Costs, Share-based Payments [Text Block] us-gaap_EarningsPerShareBasic Basic (in dollars per share) JPMorgan Chase Bank [Member] Represents the legal entity, JPMorgan Chase Bank, N.A. Senior Credit Facilities Due 2020 [Member] Represents the senior credit facility due in 2020. cabo_LongTermDebtAmortizationRateFirstTwelveMonths Long Term Debt, Amortization Rate, First Twelve Months Represents the long term debt amortization rate, as a percentage, for the first twelve months. cabo_LongTermDebtAmortizationRateYearThree Long Term Debt, Amortization Rate, Year Three Represents the debt amortization rate, as a percentage, for year three. Statement [Table] cabo_LongTermDebtAmortizationRateYearTwo Long Term Debt, Amortization Rate, Year Two Represents the long term debt amortization rate, as a percentage, for year two. cabo_LongTermDebtAmortizationRateYearFive Long Term Debt, Amortization Rate, Year Five Represents the debt amortization, as a percentage, in year five. cabo_LongTermDebtAmortizationRateYearFour Long Term Debt, Amortization Rate, Year Four Represents the amortization rate, as a percentage, for year four. Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] cabo_CreditFacilityMaximumAdditionalAmountAllowable Credit Facility, Maximum Additional Amount Allowable Represents the maximum amount of additional credit facilities the company can seek per the covenants in the current credit facility. The 2015 Plan [Member] Represents the 2015 equity-based compensation plan. cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAuthorizedForIncentiveStockOptions Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Authorized for Incentive Stock Options Represents the Maximum number of shares authorized for the incentive stock options for the equity based compensation plan. Commitments and Contingencies Disclosure [Text Block] us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit Goodwill, Written off Related to Sale of Business Unit Other liabilities Income Statement [Abstract] Cash flows from financing activities: Condensed Income Statement [Table Text Block] Deferred income taxes us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability Deferred Compensation Arrangement with Individual, Recorded Liability us-gaap_DeferredCompensationArrangementWithIndividualMaximumContractualTerm1 Deferred Compensation Arrangement with Individual, Maximum Contractual Term Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Letter of Credit [Member] Title of Individual [Axis] Relationship to Entity [Domain] Schedule of Intangible Assets and Goodwill [Table Text Block] Accrued compensation and related benefits cabo_GainLossOnDispositionOfCableSystem Gain on sale of cable system Amount of gain (loss) on sale or disposal of cable systems. Proceeds from sale of cable system The cash inflow from the sale of a cable system. cabo_PaymentsToAcquireCableSystem Acquisition of cable system The cash outflow for purchase of cable system. Senior Unsecured Notes Provision for income taxes Provision for Income Taxes Dividends [Domain] Dividends [Axis] cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVestedAndExercisableNumber Vested and exercisable, stock appreciation rights (in shares) Number of equity instruments other than options vested and exercisable. cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExercisableWeightedAverageExercisePrice Vested and exercisable, weighted average exercise price (in dollars per share) Weighted average price at which grantees can acquire the shares vested and exercisable under the equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan). cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExercisableWeightedAverageGrantDateFairValue Vested and exercisable, weighted average fair value (in dollars per share) The weighted average fair value of vested and exercisable awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan). cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedAndExercisable Vested and exercisable, aggregate intrinsic value Intrinsic value of equity-based compensation awards vested and exercisable. Excludes stock and unit options. cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExercisableWeightedAverageRemainingContractualTerms Weighted Average Remaining Contractual Term, Vested and exercisable (Year) Weighted average remaining contractual term for equity-based awards vested and exercisable, excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. us-gaap_LiabilitiesCurrent Total Current Liabilities Common Class A [Member] us-gaap_DebtInstrumentTerm Debt Instrument, Term Common Class B [Member] Quarterly Financial Information [Text Block] Class of Stock [Axis] Class of Stock [Domain] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Deferred revenue Long-term debt - current portion Less current portion long-term debt cabo_DeferredCompensationArrangementCompensationExpenseIncome Deferred Compensation Arrangement, Compensation Expense (Income) Amount of expense (income) on deferred compensation arrangement during the period. Multiemployer Plans, Postretirement Benefit [Member] Multiemployer Plan Type [Axis] Multiemployer Plans Type [Domain] Schedule of Maturities of Long-term Debt [Table Text Block] us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount Defined Contribution Plan, Employer Discretionary Contribution Amount Notes [Member] Represents notes payable. Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] Term Loan [Member] Represents term loan. Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 Debt Instrument, Basis Spread on Variable Rate Schedule of Share-based Compensation, Stock Appreciation Rights Award Activity [Table Text Block] us-gaap_DefinedContributionPlanCostRecognized Defined Contribution Plan, Cost Recognized Defined Contribution Plan Name [Domain] us-gaap_DebtInstrumentInterestRateEffectivePercentage Debt Instrument, Interest Rate, Effective Percentage us-gaap_DebtInstrumentInterestRateStatedPercentage Debt Instrument, Interest Rate, Stated Percentage Defined Contribution Plan Name [Axis] Accounts payable and accrued liabilities Total accounts payable and accrued liabilities us-gaap_DefinedBenefitPlanContributionsByEmployer Defined Benefit Plan, Contributions by Employer us-gaap_TaxesPayableCurrent Accrued sales and other operating taxes us-gaap_DebtInstrumentFaceAmount Debt Instrument, Face Amount Income taxes payable cabo_FinitelivedIntangibleAssetsAmortizationExpenseAfterYearThree Finite-Lived Intangible Assets, Amortization Expense, after Year Three Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. us-gaap_EmployeeRelatedLiabilitiesCurrent Accrued compensation and related benefits us-gaap_AccountsPayableCurrent Accounts payable Subsequent Event [Member] Schedule of Expected Benefit Payments [Table Text Block] us-gaap_CapitalLeaseObligationsIncurred Equipment financed with capital lease Subsequent Event Type [Axis] Subsequent Event Type [Domain] New Wave [Member] Represents the acquisition of New Wave. Proceeds from sales of intangible assets Non-cash investing and financing activity: Schedule of Changes in Projected Benefit Obligations [Table Text Block] Subsequent Events [Text Block] Proceeds from sales of property, plant and equipment and other Supplemental cash flow disclosures: us-gaap_LiabilitiesFairValueDisclosure Long-term debt, including current portion London Interbank Offered Rate (LIBOR) [Member] Debt Instrument [Axis] Debt Instrument, Name [Domain] Schedule of Amounts Recognized in Balance Sheet [Table Text Block] us-gaap_OtherAccruedLiabilitiesCurrent Other accrued expenses us-gaap_ProceedsFromSaleOfPropertyHeldForSale Proceeds from Sale of Property Held-for-sale Variable Rate [Axis] Variable Rate [Domain] Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block] Schedule of Long-term Debt Instruments [Table Text Block] Business Description and Basis of Presentation [Text Block] Liability Class [Axis] Fair Value by Liability Class [Domain] us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Capital expenditures us-gaap_GainLossOnSaleOfPropertyPlantEquipment Net loss on sales of property, plant and equipment Fair Value Inputs, Assets, Quantitative Information [Table Text Block] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Current Liabilities: Additional Parent Company Investment (Deficit) [Member] The settlement of intercompany balances and transactions between the Company and the Parent that were not historically settled in cash are included in Additional Parent Company Investment and thus effectively deemed settled in cash for presentation purposes. us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation Withholding tax for restricted stock awards Net transfers to GHC Total net transfers to GHC Represents information about the net settlements of intercompany balances and transactions between the Company and Parent. cabo_NumberOfCustomers Number of Customers Represents the number of customers. us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive 2021 Video [Member] Represents information about video services or groups of similar services that are sold by the entity. us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter 2022 - 2026 us-gaap_Assets Total Assets Data [Member] Represents information about data services or groups of similar services that are sold by the entity. us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree 2019 Voice [Member] Represents information about voice services or groups of similar services that are sold by the entity. us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour 2020 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths 2017 Revenue Disclosure [Text Block] Represents the entire disclosure of revenue by reporting categories and amounts of significant changes that occurred during the reporting period. us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo 2018 cabo_ChangeInAccruedExpensesRelatedToCapitalExpenditures Change in accrued expenses related to capital expenditures The cash outflow from the change in accrued expenses related to capital expenditures. December 31, 2015 [Member] Date the financial statement was made available and submitted. Current Assets [Member] Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment Disposal Group, Including Discontinued Operation, Property, Plant and Equipment Long-term Debt [Text Block] Reclassification of Deferred Financing Costs [Member] Description of new accounting pronouncement. cabo_SharebasedCompensationArrangementsBySharebasedPaymentAwardVestingPeriodNumberOfInstallments Share-based Compensation Arrangements by Share-based Payment Award, Vesting Period, Number of Installments The number of installments in which an employee award vests. cabo_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndUnissued Vested and unissued, restricted stock (in shares) The number of equity-based payment instruments, excluding stock (or unit) options, that vested but are still unissued during the reporting period. cabo_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndUnissuedWeightedAverageGrantDateFairValue Vested and unissued, weighted average grant date fair value (in dollars per share) Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that are vested but unissued. Commercial [Member] Represents information about the commercial subscribers. Effect of dilutive equity awards (1) (in shares) Building and Leasehold Improvements[Member] Represents information about the facility held for productive use including, but not limited to, office, production, storage and distribution facilities and also, additions or improvements to assets held under a lease arrangement. Related Party Transactions Disclosure and Parent Company Equity [Text Block] The entire disclosure for related party transactions and parent company equity. Schedule of Net Transfers to Parent [Table Text Block] Tabular disclosure of net transfers to parent. cabo_AdvancesToParent Net advances to GHC Represents information about the amount of advances to parent. us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation Shares Paid for Tax Withholding for Share Based Compensation Withholding tax for restricted stock awards (in shares) cabo_SharebasedCompensationArrangementsBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresInPeriodWeightedAverageExercisePrice Forfeited, weighted average exercise price (in dollars per share) Weighted average per share amount of forfeited share-based compensation awards. Net change in current income tax accounts Represents information about the net settlements of intercompany balances and transactions related to the change in current income tax accounts between the Company and the Parent. Allocation of overhead and other expenses from GHC Allocation of Overhead and Other Expenses from Parent Represents information about the allocation of overhead and other expenses from the Parent to the Company. cabo_AnnualRetainer Annual Retainer Retainer amount paid each year to non-employee director under Director Compensation Program. Dividends Paid to GHC [Member] Represents dividends paid to GHC. us-gaap_SharesIssued Balance (in shares) Balance (in shares) cabo_AdditionalAnnualRetainer Additional Annual Retainer Additional retainer amount paid each year to non-employee director under Director Compensation Program. Dividends Paid to Shareholders [Member] Represents dividends paid to shareholders. us-gaap_IncomeTaxReceivable Income Taxes Receivable us-gaap_LineOfCreditFacilityCommitmentFeePercentage Line of Credit Facility, Commitment Fee Percentage Depreciation and amortization cabo_ShareBasedCompensationArrangementsByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice Granted, weighted average exercise price (in dollars per share) Weighted average per share amount at which grantees can acquire shares of common stock by exercise of other than stock (or unit) options (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity Line of Credit Facility, Remaining Borrowing Capacity cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageExercisePrice Outstanding, weighted average exercise price (in dollars per share) Outstanding, weighted average exercise price (in dollars per share) Weighted average price at which grantees can acquire the shares reserved for issuance under the equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan). us-gaap_AmortizationOfIntangibleAssets Amortization of Intangible Assets Seven Year Term B Loans [Member] Represents the seven-year term "B" loans. us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Line of Credit Facility, Maximum Borrowing Capacity Five Year Term A Loans [Member] Represents the five-year term "A" loans. Multiemployer Plans, Savings [Member] Savings plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. Intangibles, net Accumulated Amortization Money Market Funds [Member] Defined Benefit Supplemental Executive Retirement Plan [Member] Information by Supplemental Executive Retirement Plan. Net Carrying Amount us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Gross Carrying Amount Net income Net income Net income us-gaap_AdvertisingExpense Advertising Expense Interest cost Lender Name [Axis] Line of Credit Facility, Lender [Domain] Stock Appreciation Rights (SARs) [Member] Restricted Stock Units (RSUs) [Member] us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation Defined Benefit Plan, Accumulated Benefit Obligation Goodwill Goodwill Actuarial loss recognition us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment Less accumulated depreciation Restricted Stock [Member] Property, plant and equipment, net Property, plant and equipment gross cabo_DefinedContributionPlanBenefitObligation Defined Contribution Plan, Benefit Obligation The projected benefit obligation for a defined contribution plan. Property, plant and equipment gross us-gaap_GainLossOnDispositionOfIntangibleAssets Gain (Loss) on Disposition of Intangible Assets Net gain on sale of intangible assets Revenue from External Customers by Products and Services [Table Text Block] Selling, general and administrative us-gaap_ProvisionForDoubtfulAccounts Charged to costs and expenses us-gaap_Dividends Dividends us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements us-gaap_DefinedBenefitPlanBenefitsPaid Benefits paid Use of Estimates, Policy [Policy Text Block] Cash flows from investing activities: New Accounting Pronouncements, Policy [Policy Text Block] us-gaap_NumberOfReportableSegments Number of Reportable Segments us-gaap_DefinedBenefitPlanBenefitObligation Defined Benefit Plan, Benefit Obligation Benefit obligation at Beginning of Period (1) Benefit Obligation at End of Year Earnings Per Share [Text Block] Operating (excluding depreciation and amortization) Operating costs and expenses Represents the total amount of operating costs and expenses excluding depreciation and amortization expenses. us-gaap_PriorPeriodReclassificationAdjustment Prior Period Reclassification Adjustment cabo_ProceedsFromPaymentsToParent Net transfers to GHC The net cash inflow or outflow from parent. Net income per common share: us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet Other assets and other liabilities, net Costs and Expenses