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Note 7 - Goodwill and Intangible Assets Note 8 - Long-term Debt us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets Prepaid and other current assets Note 9 - Fair Value Measurements us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables Accounts receivable Income Tax Disclosure [Text Block] Note 11 - Equity-based Compensation Note 13 - Net Income Per Common Share us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents Cash and cash equivalents Note 2 - Revision of Previously Issued Financial Statements - Revisions on Consolidated Financial Statements (Details) Expected volatility Note 3 - Adoption of New Revenue Recognition Standard - Impact of ASC 606 Adoption (Details) Total Current Liabilities Total Current Liabilities Note 4 - NewWave Acquisition - Allocation of Purchase Price Consideration (Details) Schedule of Maturities of Long-term Debt [Table Text Block] Note 5 - Revenues - Revenues by Product Line (Details) Note 6 - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) Note 7 - Goodwill and Intangible Assets - Intangible Assets (Details) Note 7 - Goodwill and Intangible Assets - Amortization of Intangible Assets (Details) Expected term (Year) Note 8 - Long-term Debt - Schedule of Long-term Debt (Details) Note 8 - Long-term Debt - Future Maturities (Details) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms Weighted average remaining contractual term, outstanding (Year) Note 9 - Fair Value Measurements - Carrying Amounts and Fair Values (Details) Note 11 - Equity-based Compensation - Restricted Stock (Details) Note 11 - Equity-based Compensation - Stock Appreciation Rights (Details) 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. 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. 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stock (in shares) Current portion of long-term debt Less current portion Accounts payable and accrued liabilities Deferred revenue us-gaap_ContractWithCustomerLiabilityCurrent Contract with Customer, Liability, Current us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber Outstanding, stock appreciation rights (in shares) Outstanding, stock appreciation rights (in shares) Goodwill and Intangible Assets Disclosure [Text Block] Secured Debt [Member] Revolving Credit Facility [Member] Credit Facility [Axis] Proceeds from sales of property, plant and equipment Credit Facility [Domain] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_ProceedsFromSaleOfPropertyHeldForSale Proceeds from Sale of Property Held-for-sale Trademarks and Trade Names [Member] Franchise Rights [Member] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Capital expenditures Effect of dilutive equity awards (in shares) Use Rights [Member] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Product and Service, Other [Member] Liabilities and Stockholders' Equity Weighted average common shares outstanding: Treasury Stock [Text Block] Total Assets Total Assets Supplemental cash flow disclosures: Long-term debt, including current portion us-gaap_LongTermDebtFairValue Plan Name [Axis] Plan Name [Domain] us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment Disposal Group, Including Discontinued Operation, Property, Plant and Equipment us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1 Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Customer Relationships [Member] us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense Employee Service Share-based Compensation, Tax Benefit from Compensation Expense us-gaap_CapitalizedContractCostNet Capitalized Contract Cost, Net, Total Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation Withholding tax for equity awards Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] Adjustments for Error Corrections [Axis] Adjustments for Error Correction [Domain] Business Description and Basis of Presentation [Text Block] Equity Award [Domain] Award Type [Axis] Net income Net income Accumulated amortization Net carrying amount Total Intangible assets, net Stock Appreciation Rights (SARs) [Member] Restricted Stock Units (RSUs) [Member] Gross carrying amount, amortized intangible assets Advertising [Member] us-gaap_GoodwillAcquiredDuringPeriod Goodwill, Acquired During Period Gross carrying amount, indefinite-lived intangible assets Commitments and Contingencies Disclosure [Text Block] Business Combination Disclosure [Text Block] us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment Less: Accumulated depreciation Property, plant and equipment, net Property, plant and equipment, net Goodwill Goodwill, Ending Balance Property, plant and equipment, gross Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] us-gaap_Dividends Dividends paid to stockholders Cash flows from investing activities: us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet Other noncurrent assets and liabilities, net Net income per common share: Earnings Per Share [Text Block] us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities Accounts payable and accrued liabilities Letter of Credit [Member] Income tax provision us-gaap_DebtInstrumentTerm Debt Instrument, Term Cash and cash equivalents us-gaap_CashAndCashEquivalentsAtCarryingValue Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period us-gaap_AllocatedShareBasedCompensationExpense Allocated Share-based Compensation Expense, Total Amendment Flag Comprehensive income Comprehensive income Use of Estimates, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] us-gaap_GainLossOnSaleOfPropertyPlantEquipment Gain (Loss) on Disposition of Property Plant Equipment, Total us-gaap_TreasuryStockSharesAcquired Treasury Stock, Shares, Acquired Repurchases of common stock (in shares) Common stock, shares outstanding (in shares) Preferred stock, shares outstanding (in shares) Current Fiscal Year End Date us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 Debt Instrument, Basis Spread on Variable Rate us-gaap_DebtInstrumentInterestRateStatedPercentage Debt Instrument, Interest Rate, Stated Percentage us-gaap_DebtInstrumentInterestRateEffectivePercentage Debt Instrument, Interest Rate, Effective Percentage us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets Prepaid and other current assets Document Fiscal Period Focus Document Fiscal Year Focus Consolidation, Policy [Policy Text Block] Document Period End Date us-gaap_DebtInstrumentFaceAmount Debt Instrument, Face Amount Write-off of debt issuance costs Document Type us-gaap_NumberOfStatesInWhichEntityOperates Number of States in which Entity Operates us-gaap_AssetImpairmentCharges Asset Impairment Charges, Total Document Information [Line Items] Document Information [Table] Entity Filer Category Debt Instrument [Axis] Entity Current Reporting Status Debt Instrument, Name [Domain] Entity Voluntary Filers Entity Well-known Seasoned Issuer London Interbank Offered Rate (LIBOR) [Member] Variable Rate [Domain] Schedule of Long-term Debt Instruments [Table Text Block] us-gaap_IncreaseDecreaseInIncomeTaxesReceivable Income taxes receivable Variable Rate [Axis] us-gaap_CapitalizedContractCostAmortization Capitalized Contract Cost, Amortization 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. Change in accounts receivable, net Accounts receivable, net Equity-based compensation Entity Central Index Key Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction, Total cabo_DebtInstrumentCovenantFirstLienNetLeverageRatio Debt Instrument, Covenant, Maximum First Lien Net Leverage Ratio The maximum first lien net leverage ratio that must be met in order to obtain additional credit facilities. Entity Registrant Name Liability Class [Axis] Fair Value by Liability Class [Domain] Entity [Domain] us-gaap_CapitalizedContractCostAmortizationPeriod Capitalized Contract Cost, Amortization Period Legal Entity [Axis] us-gaap_AmortizationOfIntangibleAssets Amortization of Intangible Assets, Total us-gaap_TreasuryStockValueAcquiredCostMethod Treasury Stock, Value, Acquired, Cost Method Repurchases of common stock us-gaap_TreasuryStockValue Treasury stock, at cost (184,562 and 156,457 shares held as of June 30, 2018 and December 31, 2017, respectively) Entity Common Stock, Shares Outstanding (in shares) Long-term Debt [Text Block] Trading Symbol us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity Line of Credit Facility, Remaining Borrowing Capacity us-gaap_TableTextBlock Notes Tables us-gaap_GainLossOnDispositionOfAssets1 (Gain) loss on disposal of assets, net us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Line of Credit Facility, Maximum Borrowing Capacity Issuance of equity awards, net of forfeitures (in shares) Selling, general and administrative Selling, General and Administrative Expense, Total Line of Credit Facility, Lender [Domain] Lender Name [Axis] Total Liabilities and Stockholders' Equity Total Liabilities and Stockholders' Equity Reported Value Measurement [Member] Retained earnings Accumulated other comprehensive loss Costs and expenses Money Market Funds [Member] us-gaap_InterestExpense Interest expense Changes in operating assets and liabilities, net of effects from acquisitions: Amortization of debt issuance cost Amortization of Debt Issuance Costs us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements Change in deferred income taxes Thereafter 2018 (remaining six months) 2019 2020 2021 2022 Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Segment Reporting, Policy [Policy Text Block] Other noncurrent assets us-gaap_ShareBasedCompensation Equity-based compensation Useful life (Year) us-gaap_Depreciation Depreciation, Total us-gaap_DepreciationDepletionAndAmortization Depreciation and amortization us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation Shares Paid for Tax Withholding for Share Based Compensation Withholding tax for equity awards (in shares) us-gaap_SharesIssued Balance (in shares) Balance (in shares) Total Current Assets Total Current Assets Cash and cash equivalents us-gaap_CashAndCashEquivalentsFairValueDisclosure Income taxes receivable Treasury stock, shares (in shares) Treasury Stock, Shares, Ending Balance Common stock ($0.01 par value; 40,000,000 shares authorized; 5,887,899 shares issued; and 5,703,337 and 5,731,442 shares outstanding as of June 30, 2018 and December 31, 2017, respectively) Adjustments to reconcile net income to net cash provided by operating activities: Common stock, shares authorized (in shares) Commercial Paper [Member] Common stock, shares issued (in shares) Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Common stock, par value (in dollars per share) Restatement [Axis] Restatement [Domain] Previously Reported [Member] Restatement Adjustment [Member] Range [Domain] Maximum [Member] Minimum [Member] us-gaap_CapitalizedContractCostNetCurrent Capitalized Contract Cost, Net, Current Product and Service [Axis] Product and Service [Domain] Range [Axis] Preferred stock ($0.01 par value; 4,000,000 shares authorized; none issued or outstanding) Preferred stock, shares issued (in shares) Cash paid for interest, net of capitalized interest Cash paid for income taxes, net of refunds received Property, Plant and Equipment Disclosure [Text Block] Property, Plant and Equipment [Table Text Block] Preferred stock, shares authorized (in shares) Portion at Fair Value Measurement [Member] [Default] Preferred stock, par value (in dollars per share) Estimate of Fair Value Measurement [Member] Revenues Revenues Revenue from Contract with Customer, Including Assessed Tax Measurement Basis [Axis] Revenue from External Customers by Products and Services [Table Text Block] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value Hierarchy and NAV [Axis] Software and Software Development Costs [Member] Change in deferred revenue Deferred revenue Construction in Progress [Member] Cash flows from operating activities: Accounts receivable, net Other Capitalized Property Plant and Equipment [Member] Senior Unsecured Notes Due 2022 [Member] Represents the senior unsecured notes due 2022. Revenue Recognition, Policy [Policy Text Block] Statement [Line Items] Furniture and Fixtures [Member] us-gaap_NumberOfReportableSegments Number of Reportable Segments us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Additional paid-in capital Residential JPMorgan Chase Bank [Member] Represents the legal entity, JPMorgan Chase Bank, N.A. AOCI Attributable to Parent [Member] Stockholders' Equity Exercised, weighted average exercise price (in dollars per share) cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisesInPeriodWeightedAverageExercisePrice Weighted average per share amount at which exercisors 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). Senior Credit Facilities Due 2020 [Member] Represents the senior credit facility due in 2020. Land [Member] cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisesInPeriodWeightedAverageGrantDateFairValue Exercised, weighted average fair value (in dollars per share) The weighted average fair value for equity-based awards exercised during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisesInPeriod Exercised, stock appreciation rights (in shares) The number of exercises made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Adjustments for Change in Accounting Principle [Axis] Other income (expense), net Adjustments for Change in Accounting Principle [Domain] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] 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. cabo_LongTermDebtAmortizationRateYearTwo Long Term Debt, Amortization Rate, Year Two Represents the long term debt amortization rate, as a percentage, for year two. Fair Value Disclosures [Text Block] cabo_LongTermDebtAmortizationRateYearFour Long Term Debt, Amortization Rate, Year Four Represents the amortization rate, as a percentage, for year four. The 2015 Plan [Member] Represents the 2015 equity-based compensation plan. Assets Incremental Term Loan A [Member] Information pertaining to Incremental Term Loan A. Incremental Term Loan B [Member] Information pertaining to Incremental Term Loan B. Total Liabilities Total Liabilities us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash provided by (used in) financing activities Commitments and contingencies (refer to note 14) cabo_DebtInstrumentAmortizationPercentOnAQuarterlyBasis Debt Instrument, Amortization Percent on a Quarterly Basis Represents the quarterly amortization of the debt instrument expressed as a percentage of the original principal amount. cabo_DebtInstrumentPrepaymentPenaltyPrepaidWithinSixMonthsPercent Debt Instrument, Prepayment Penalty, Prepaid within Six Months, Percent Represents the percentage of the prepayment penalty of the debt instrument if prepaid within six months of funding. Income from operations Income from operations Net cash provided by operating activities Net cash provided by operating activities Prepaid and other current assets us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used in investing activities us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease Change in cash and cash equivalents Base Rate [Member] us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent Deferred Compensation Liability, Current and Noncurrent, Total Headquarters Building and Adjoining Property [Member] Information pertaining to the headquarters building and adjoining property. us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation Payments Related to Tax Withholding for Share-based Compensation Payment of withholding tax for equity awards us-gaap_LettersOfCreditOutstandingAmount Letters of Credit Outstanding, Amount us-gaap_PaymentsOfDividends Dividends paid to stockholders Total costs and expenses Total costs and expenses us-gaap_PaymentsForRepurchaseOfCommonStock Repurchases of common stock Retained Earnings [Member] Treasury Stock [Member] Vested and exercisable, stock appreciation rights (in shares) cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVestedAndExercisableNumber Number of equity instruments other than options vested and exercisable. Additional Paid-in Capital [Member] Vested and exercisable, weighted average exercise price (in dollars per share) cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExercisableWeightedAverageExercisePrice 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). Common Stock [Member] us-gaap_StockRepurchaseProgramAuthorizedAmount1 Stock Repurchase Program, Authorized Amount 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). us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased Stock Repurchase Program, Number of Shares Authorized to be Repurchased cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedAndExercisable Vested and exercisable, aggregate intrinsic value Intrinsic value of equity-based compensation awards vested and exercisable. Excludes stock and unit options. Equity Components [Axis] 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. Equity Component [Domain] us-gaap_LongTermDebt Total Capital lease obligation Other Noncurrent Assets [Member] Senior Credit Facilities [Member] Represents senior credit facilities. us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1 Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Other Noncurrent Liabilities [Member] Income before income taxes Income before income taxes us-gaap_PaymentsOfDebtIssuanceCosts Payment of debt issuance costs us-gaap_DeferredFinanceCostsNet Debt Issuance Costs, Net, Total Less unamortized debt issuance costs us-gaap_RepaymentsOfLongTermDebt Payments on long-term debt Equipment [Member] Revenue from Contract with Customer [Text Block] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Senior Credit Facilities us-gaap_DebtInstrumentCarryingAmount Long-term Debt, Gross Accounting Policies [Abstract] Basis of Accounting, Policy [Policy Text Block] Notes [Member] Represents notes payable. Selling, General and Administrative Expenses [Member] Term Loan [Member] Represents term loan. Dividends declared per common share (in dollars per share) Long-term debt Total long-term debt Total debt us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities Proceeds from issuance of long-term debt Income Statement Location [Axis] Income Statement Location [Domain] New Wave [Member] Represents the acquisition of New Wave. us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Diluted (in shares) Weighted average common shares outstanding - diluted (in shares) Scenario, Forecast [Member] Asset Class [Axis] Asset Class [Domain] Statement [Table] Scenario [Axis] Statement of Financial Position [Abstract] cabo_NumberOfCustomers Number of Customers Represents the number of customers. Scenario, Unspecified [Domain] Diluted (in dollars per share) Basic (in shares) Video [Member] Represents information about video services or groups of similar services that are sold by the entity. Data [Member] Represents information about data services or groups of similar services that are sold by the entity. Voice [Member] Represents information about voice services or groups of similar services that are sold by the entity. us-gaap_EffectiveIncomeTaxRateContinuingOperations Effective Income Tax Rate Reconciliation, Percent, Total Change in cash overdraft Business Acquisition [Axis] Schedule of Share-based Payment Award, Other than Options, Valuation Assumptions [Table Text Block] Tabular disclosure of the significant assumptions used during the year to estimate the fair value of awards excluding options (for example, stock appreciation rights, restricted stock, phantom stock), including, but not limited to: (a) expected term of awards, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. cabo_ChangeInAccruedExpensesRelatedToCapitalExpenditures Change in accrued expenses related to capital expenditures The cash outflow from the change in accrued expenses related to capital expenditures. Basic (in dollars per share) Business Acquisition, Acquiree [Domain] Change in Accounting Principle for the Capitalization of Certain Labor and Supervisory Activities [Member] Refers to the information regarding the change in accounting principle for the capitalization of certain labor and supervisory activities. Statement of Cash Flows [Abstract] cabo_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedLiabilities Accounts payable and accrued liabilities Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables and accrued liabilities, assumed at the acquisition date. us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear 2018 (remaining six months) 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. Vested and unissued, restricted stock, 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. Statement of Stockholders' Equity [Abstract] 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. Income Statement [Abstract] Changes in pension, net of tax Other comprehensive gain (loss), net of tax us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree 2020 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour 2021 Fees Imposed by Various Governmental Authorities Passed Through to Customer [Member] Represents the fees imposed on the company by various governmental authorities are passed through monthly to the company's customers and are periodically remitted to authorities. us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive 2022 Forfeited, weighted average exercise price (in dollars per share) cabo_SharebasedCompensationArrangementsBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresInPeriodWeightedAverageExercisePrice Weighted average per share amount of forfeited share-based compensation awards. us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive Thereafter us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo 2019 Granted, weighted average exercise price (in dollars per share) cabo_ShareBasedCompensationArrangementsByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice 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). 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). cabo_OptionalAdditionalAvailableCreditFacilities Optional Additional Available Credit Facilities The amount of additional credit facilities available to the Company, at the Company’s option, subject to compliance with certain financial covenants. Schedule of Intangible Assets and Goodwill [Table Text Block] New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Cash flows from financing activities: us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Other noncurrent liabilities Accounting Changes and Error Corrections [Text Block] Deferred income taxes Business Services [Member] Represents the information pertaining to business services. us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet Net Assets Acquired us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet Purchase price consideration us-gaap_ContractWithCustomerLiabilityNoncurrent Contract with Customer, Liability, Noncurrent Total Stockholders' Equity Total Stockholders' Equity Balance Balance us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities Total Liabilities Assumed us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired Purchase of business, net of cash acquired Class of Stock [Axis] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent Deferred income taxes Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue Deferred revenue us-gaap_PaymentsToAcquireBusinessesGross Payments to Acquire Businesses, Gross us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets Total Assets Acquired Notes Operating (excluding depreciation and amortization) Operating Expenses Excluding Depreciation and Amortization Represents the total amount of operating costs and expenses excluding depreciation and amortization expenses. us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment Property, plant and equipment us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets Other noncurrent assets