Document And Entity Information Note To Financial Statement Details Textual Derivative, Notional Amount us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill Intangible assets Significant Accounting Policies Note 2 - Acquisitions Note 3 - Revenues Hedging Relationship [Domain] Note 4 - Operating Assets and Liabilities Note 5 - Property, Plant and Equipment Cash Flow Hedging [Member] Note 6 - Goodwill and Intangible Assets Note 7 - Debt Note 8 - Interest Rate Swaps 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 Hedging Relationship [Axis] Unrealized loss on cash flow hedges and other, net of tax Represents the after tax and reclassification, of deferred gain (loss) on cash flow hedges and other including pension change. Note 13 - Net Income Per Common Share Note 2 - Acquisitions - Change in Goodwill (Details) us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents Cash and cash equivalents Note 2 - Acquisitions - Allocation of Purchase Price Consideration (Details) us-gaap_LiabilitiesCurrent Total Current Liabilities Note 3 - Revenues - Revenues by Product Line (Details) Schedule of Maturities of Long-term Debt [Table Text Block] Note 4 - Operating Assets and Liabilities - Summary of Accounts Receivable (Details) Note 4 - Operating Assets and Liabilities - Allowance for Doubtful Accounts (Details) us-gaap_GuaranteeObligationsMaximumExposure Letters of Credit Outstanding, Amount Note 4 - Operating Assets and Liabilities - Prepaid and Other Current Assets (Details) Note 4 - Operating Assets and Liabilities - Other Noncurrent Assets (Details) Note 4 - Operating Assets and Liabilities - Accounts Payable and Accrued Liabilities (Details) Note 4 - Operating Assets and Liabilities - Other Noncurrent Liabilities (Details) Note 5 - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms Weighted average remaining contractual term, outstanding (Year) Note 6 - Goodwill and Intangible Assets - Intangible Assets (Details) Note 6 - Goodwill and Intangible Assets - Amortization of Intangible Assets (Details) cabo_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageGrantDateFairValue 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. Note 7 - Debt - Schedule of Long-term Debt (Details) 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. us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding Outstanding, aggregate intrinsic value Note 7 - Debt - Summary of Term Loans (Details) Note 7 - Debt - Future Maturities (Details) Share-based Payment Arrangement, Stock Appreciation Right, Activity [Table Text Block] Note 8 - Interest Rate Swaps - Interest Rate Swap Agreements (Details) Note 8 - Interest Rate Swaps - Intersest Rate Swaps on the Condensed Consolidated Balance Sheets and Statements of Operations and Comprehensive Income (Details) Note 9 - Fair Value Measurements - Carrying Amounts and Fair Values (Details) Note 11 - Equity-based Compensation - Restricted Stock (Details) Granted, restricted stock, weighted avergae grant date fair value (in dollars per share) Granted, weighted average fair value (in dollars per share) Note 11 - Equity-based Compensation - Stock Appreciation Rights (Details) Interest rate swap liability Derivative liability Vested and issued, restricted stock, weighted average grant date fair value (in dollars per share) Note 13 - Net Income Per Common Share - Computation of Basic and Diluted Earnings Per Share (Details) Forfeited, restricted stock, weighted average grant date fair value (in dollars per share) Forfeited, weighted average fair value (in dollars per share) Notes To Financial Statements Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Unvested, restricted stock, weighted avergae grant date fair value (in dollars per share) Notes To Financial Statements [Abstract] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod Forfeited, restricted stock (in shares) Forfeited, stock appreciation rights (in shares) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber Unvested, restricted stock (in shares) Unvested, restricted stock (in shares) Schedule of Derivative Instruments [Table Text Block] Current portion of long-term debt Less: Current portion of long-term debt Granted, stock appreciation rights (in shares) Granted, restricted stock (in shares) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod Vested and issued, restricted stock (in shares) Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Domain] Right-of-use Assets [Member] Represents Right-of-use (“ROU”) assets. Total accounts payable and accrued liabilities 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] Schedule of Goodwill [Table Text Block] Accrued sales and other operating taxes us-gaap_TaxesPayableCurrent Accrued compensation and related benefits us-gaap_EmployeeRelatedLiabilitiesCurrent Accounts payable us-gaap_AccountsPayableCurrent Secured Debt [Member] Revolving Credit Facility [Member] Credit Facility [Axis] Proceeds from sales of property, plant and equipment Credit Facility [Domain] Operating Assets and Liabilities [Text Block] The entire disclosure of operating assets and liabilities. Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] All other accrued liabilities us-gaap_OtherAccruedLiabilitiesCurrent us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_ProceedsFromSaleOfPropertyHeldForSale Proceeds from Sale of Property Held-for-sale Trademarks and Trade Names [Member] Trade Names [Member] Franchise Rights [Member] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) Accrued insurance costs us-gaap_AccruedInsuranceCurrent Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Capital expenditures Effect of dilutive equity-based compensation awards (in shares) Use Rights [Member] Cash paid for income taxes, net of refunds received Product and Service, Other [Member] Current Liabilities: Weighted average common shares outstanding: Treasury Stock [Text Block] us-gaap_HostingArrangementServiceContractImplementationCostCapitalizedBeforeAccumulatedAmortization Capitalized Contract Cost, Net, Total us-gaap_Assets Total Assets Supplemental cash flow disclosures: Long-term debt, including current portion Plan Name [Axis] Plan Name [Domain] us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1 Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) Customer Relationships [Member] us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense Share-based Payment Arrangement, Expense, Tax Benefit us-gaap_CapitalizedContractCostNet Capitalized Contract Cost, Net, Total Share-based Payment Arrangement [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 us-gaap_ContractWithCustomerAssetNet Contract with Customer, Asset, after Allowance for Credit Loss, Total Business Description and Basis of Presentation [Text Block] Award Type [Domain] Award Type [Axis] Net income Net income Gross carrying amount, amortized intangible assets us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization Net carrying amount Total Intangible assets, net Stock Appreciation Rights (SARs) [Member] Financial Standby Letter of Credit [Member] Restricted Stock Units (RSUs) [Member] Gross carrying amount, amortized intangible assets Prepaid software Amount of prepaid software. Prepaid and Other Current Assets [Table Text Block] Tabular disclosure of prepaid and other current assets. Acquisition goodwill recognized Deferred commissions Amount of deferred commissions classified as current. Indefinite-Lived Intangible Assets cabo_DeferredCommissionsNoncurrent Deferred commissions Amount of deferred commissions classified as noncurrent. Business Combination Disclosure [Text Block] Commitments and Contingencies Disclosure [Text Block] us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment Less: Accumulated depreciation and amortization Property, plant and equipment, net Property, plant and equipment, net Goodwill Goodwill, Ending Balance Balance at December 31, 2018 Balance at December 31, 2019 Property, plant and equipment, gross Long-term Debt, Type [Axis] Term Loan A-2 [Member] Represents Term Loan A-2. Long-term Debt, Type [Domain] Term Loan Borrowings [Member] Represents term loan borrowings. us-gaap_Dividends Dividends paid to stockholders Amortization Per Annum cabo_LongTermDebtAmortizationRate Represents the long term debt amortization rate. Summary of Term Loans [Table Text Block] Tabular disclosure of summary of term loans. 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). Accrued programming costs cabo_ProgrammingCostsCurrent 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). Derivative Instrument [Axis] Derivative Contract [Domain] Cash flows from investing activities: Accrued franchise fees cabo_FranchiseFeesCurrent 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). cabo_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueExercised Exercised, aggregate intrinsic value Intrinsic value of exercised award under share-based payment arrangement. Excludes share and unit options. us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet Other, net Net income per common share: Earnings Per Share [Text Block] Increase (decrease) in accounts payable and accrued liabilities Letter of Credit [Member] Income tax provision Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax Less: Tax effect CoBank, ACB [Member] Represents information about CoBank, ACB as the lender. Term B-2 Loan [Member] Represents information about Term B-2 Loan. us-gaap_DebtInstrumentTerm Debt Instrument, Term (Year) Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period us-gaap_AllocatedShareBasedCompensationExpense Share-based Payment Arrangement, Expense Common Stock Outstanding [Member] Represents information about common stock outstanding. Amendment Flag us-gaap_ComprehensiveIncomeNetOfTax Comprehensive income (loss) City Area Code 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 (in shares) Repurchases of common stock (in shares) Increase in deferred revenue Common stock, shares outstanding (in shares) Preferred stock, shares outstanding (in shares) Current Fiscal Year End Date Applicable Margin us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 Debt Instrument, Basis Spread on Variable Rate Interest Rate us-gaap_DebtInstrumentInterestRateEffectivePercentage us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets Increase in prepaid and other current assets Document Fiscal Period Focus Document Fiscal Year Focus Consolidation, Policy [Policy Text Block] Increase in deferred income taxes us-gaap_IncreaseDecreaseInDeferredIncomeTaxes Document Period End Date Entity File Number Entity Emerging Growth Company Original Principal us-gaap_DebtInstrumentFaceAmount Debt Instrument, Face Amount Document Type us-gaap_NumberOfStatesInWhichEntityOperates Number of States in which Entity Operates Entity Small Business Entity Shell Company Document Information [Line Items] Document Information [Table] Entity Filer Category Debt Instrument [Axis] Entity Current Reporting Status Debt Instrument, Name [Domain] London Interbank Offered Rate (LIBOR) [Member] Variable Rate [Domain] Schedule of Long-term Debt Instruments [Table Text Block] us-gaap_IncreaseDecreaseInIncomeTaxesReceivable (Increase) decrease in income taxes receivable us-gaap_GoodwillImpairmentLoss Goodwill, Impairment Loss 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. us-gaap_IncreaseDecreaseInAccountsReceivable Decrease in accounts receivable, net Equity-based compensation Entity Tax Identification Number Entity Central Index Key Depreciation and amortization Entity Registrant Name Liability Class [Axis] Fair Value by Liability Class [Domain] Entity [Domain] us-gaap_CapitalizedContractCostAmortizationPeriod Capitalized Contract Cost, Amortization Period (Month) Legal Entity [Axis] Entity Address, Address Line One us-gaap_AmortizationOfIntangibleAssets Amortization of Intangible Assets, Total us-gaap_TreasuryStockValueAcquiredCostMethod Treasury Stock, Value, Acquired, Cost Method Repurchases of common stock Entity Address, City or Town Entity Address, Postal Zip Code Entity Address, State or Province us-gaap_TreasuryStockValue Treasury stock, at cost (163,042 and 172,522 shares held as of March 31, 2020 and December 31, 2019, respectively) us-gaap_AllowanceForDoubtfulAccountsReceivable Beginning balance Ending balance Entity Common Stock, Shares Outstanding Long-term Debt [Text Block] Trading Symbol us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd Line of Credit Facility, Interest Rate at Period End Local Phone Number us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity Line of Credit Facility, Remaining Borrowing Capacity us-gaap_TableTextBlock Notes Tables us-gaap_GainLossOnDispositionOfAssets1 (Gain) loss on asset sales and disposals, net us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Line of Credit Facility, Maximum Borrowing Capacity Issuance of equity awards, net of forfeitures (in shares) Selling, general and administrative Additions - charged to costs and expenses Issuance of equity awards, net of forfeitures Line of Credit Facility, Lender [Domain] Subscriber deposits cabo_AccruedSubscriberDepositsCurrent 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). Lender Name [Axis] us-gaap_LiabilitiesAndStockholdersEquity Total Liabilities and Stockholders' Equity Reported Value Measurement [Member] Clearwave [Member] Information pertaining to the acquisition of Clearwave. Retained earnings Accumulated other comprehensive loss Accumulated other comprehensive loss Money Market Funds [Member] us-gaap_InterestExpense Interest expense Changes in operating assets and liabilities, net of effects from acquisitions: Amortization of debt issuance costs Amortization of Debt Issuance Costs us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements Derivative Instruments and Hedging Activities Disclosure [Text Block] Operating lease liabilities us-gaap_OperatingLeaseLiabilityNoncurrent Operating lease liabilities us-gaap_OperatingLeaseLiabilityCurrent Operating lease right-of-use assets Finance lease liabilities us-gaap_FinanceLeaseLiability Thereafter us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive 2020 (remaining nine months) us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear 2021 us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo 2022 us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree 2023 us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour 2024 us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Segment Reporting, Policy [Policy Text Block] Other noncurrent assets Total other noncurrent assets us-gaap_ShareBasedCompensation Equity-based compensation Useful life (Year) Note receivable Prepaid repairs and maintenance Amount of asset related to consideration paid in advance for repairs and maintenance that provides economic benefits within a future period of one year or the normal operating cycle, if longer. Investments us-gaap_Depreciation Depreciation, Total cabo_CollateralPledgedByThirdParty Collateral Pledged By Third Party Amount of collateral that has been pledged by third party to satisfy letter or credit issued for performance obligations under FCC broadband funding program. Letter of Credit Issued to Third Party for FCC Performance Obligations with Offseting Collateral [Member] Represents the letters of credit drawn for a third party for FCC performance obligations that has been offset by pledged collateral assets. us-gaap_DepreciationDepletionAndAmortization Depreciation and amortization us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation (in shares) Withholding tax for equity awards (in shares) cabo_EffectiveIncomeTaxRateReconciliationNetOperatingLossCarrybackProvisionOfCaresAct Effective Income Tax Rate Reconciliation, Net Operating Loss Carryback Provision of CARES Act Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to the net operating loss carryback provision of the CARES Act. us-gaap_SharesIssued Balance (in shares) Balance (in shares) us-gaap_AssetsCurrent Total Current Assets Cash and cash equivalents us-gaap_CashAndCashEquivalentsFairValueDisclosure cabo_OriginationOfNotesReceivable Issuance of note receivable The cash outflow for a loan, supported by a promissory note. Income taxes receivable Treasury stock, shares (in shares) Treasury Stock, Shares, Ending Balance (in shares) Common stock ($0.01 par value; 40,000,000 shares authorized; 5,887,899 shares issued; and 5,724,857 and 5,715,377 shares outstanding as of March 31, 2020 and December 31, 2019, 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) Statistical Measurement [Domain] Maximum [Member] Minimum [Member] us-gaap_CapitalizedContractCostNetCurrent Capitalized Contract Cost, Net, Current Product and Service [Axis] All other current assets Product and Service [Domain] Statistical Measurement [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 Prepaid rent 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) Prepaid insurance 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] Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption, Adjustment [Member] Construction in Progress [Member] Cash flows from operating activities: Total accounts receivable, net Accounts receivable, net Other Capitalized Property Plant and Equipment [Member] Statement [Line Items] us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent Less: Allowance for credit losses Trade receivables us-gaap_AccountsReceivableNetCurrent 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 Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] JPMorgan Chase Bank [Member] Represents the legal entity, JPMorgan Chase Bank, N.A. AOCI Attributable to Parent [Member] Term B-1 Loan [Member] Related to the term b-1 loan. 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). Stockholders' Equity 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). Other income, net Fidelity [Member] Related to Fidelity. Long-Lived Tangible Asset [Axis] Long-Lived Tangible Asset [Domain] All other noncurrent assets 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. Current Assets: cabo_LongTermDebtAmortizationRateYearTwo Long Term Debt, Amortization Rate, Year Two Represents the long term debt amortization rate, as a percentage, for year two. Schedule of Other Assets, Noncurrent [Table Text Block] Fair Value Disclosures [Text Block] 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. The 2015 Plan [Member] Represents the 2015 equity-based compensation plan. Incremental Term Loan B [Member] Information pertaining to Incremental Term Loan B. us-gaap_Liabilities Total Liabilities us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash provided by financing activities Commitments and contingencies (refer to note 14) us-gaap_OperatingIncomeLoss Income from operations us-gaap_ContractWithCustomerLiabilityRevenueRecognized Contract with Customer, Liability, Revenue Recognized us-gaap_NetCashProvidedByUsedInOperatingActivities Net cash provided by operating activities Prepaid and other current assets Total prepaid and other current assets us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used in investing activities us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease Increase (decrease) in cash and cash equivalents Deferred income taxes Headquarters Building and Adjoining Property [Member] Information pertaining to the headquarters building and adjoining property. Interest rate swaps Total All other noncurrent liabilities us-gaap_OtherSundryLiabilitiesNoncurrent Accounting Standards Update [Domain] us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation Payment, Tax Withholding, Share-based Payment Arrangement Payment of withholding tax for equity awards us-gaap_LettersOfCreditOutstandingAmount Letters of Credit Outstanding, Amount Accounting Standards Update [Axis] us-gaap_PaymentsOfDividends Dividends paid to stockholders us-gaap_CostsAndExpenses Total Costs and Expenses us-gaap_PaymentsForRepurchaseOfCommonStock Repurchases of common stock Costs and Expenses: 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). 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 (in shares) 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] Equity Component [Domain] 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. Accounts Payable and Accrued Liabilities [Member] Balance Due Upon Maturity us-gaap_LongTermDebt Total Prepaid Expenses and Other Current Assets [Member] Other Noncurrent Assets [Member] Senior Credit Facilities [Member] Represents senior credit facilities. cabo_DebtIssuanceCostsNetTotalReductionsToDebtAndOtherNoncurrent Debt Issuance Costs, Net, Total Reductions to Debt and Other, Noncurrent Noncurrent amount, after accumulated amortization, of debt issuance costs. Includes amount that is reduced from debt and other. Other Noncurrent Liabilities [Member] Accounting Standards Update 2018-15 [Member] us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest Income before income taxes us-gaap_LineOfCredit Long-term Line of Credit, Total us-gaap_PaymentsOfDebtIssuanceCosts Payment of debt issuance costs 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] Document Quarterly Report Entity Incorporation, State or Country Code Senior Credit Facilities (as defined below) us-gaap_DebtInstrumentCarryingAmount Long-term Debt, Gross Accounting Policies [Abstract] Document Transition Report Basis of Accounting, Policy [Policy Text Block] Selling, General and Administrative Expenses [Member] Entity Interactive Data Current Term Loan [Member] Represents term loan. Recoveries of amounts previously written off Dividends, per share (in dollars per share) Interest Expense [Member] Security Exchange Name Cash overdrafts us-gaap_BankOverdrafts Title of 12(b) Security us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs Deductions Long-term debt Total long-term debt Total debt us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities Proceeds from long-term debt borrowings Proceeds from Issuance of Long-term Debt, Total Income Statement Location [Axis] Income Statement Location [Domain] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Second Interest Rate Swap Agreement [Member] Information pertaining to the second interest rate swap agreement. Interest rate swaps are forward based contracts in which two parties agree to swap periodic payments that are fixed at the outset of the swap contract with variable payments based on a market interest rate (index rate) over a specified period. First Interest Rate Swap Agreement [Member] Information pertaining to the first interest rate swap agreement. Interest rate swaps are forward based contracts in which two parties agree to swap periodic payments that are fixed at the outset of the swap contract with variable payments based on a market interest rate (index rate) over a specified period. us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) Diluted (in shares) us-gaap_ProceedsFromLinesOfCredit Proceeds from Lines of Credit, Total Asset Class [Axis] Asset Class [Domain] Statement [Table] Statement of Financial Position [Abstract] cabo_NumberOfCustomers Number of Customers Represents the number of customers. 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. Term B-3 Loan [Member] Represents information about Term B-3 Loan. us-gaap_EffectiveIncomeTaxRateContinuingOperations Effective Income Tax Rate Reconciliation, Percent, Total Business Acquisition [Axis] cabo_ChangeInAccruedExpensesRelatedToCapitalExpenditures Decrease 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] 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. 2020 (remaining nine months) us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear 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. Statement of Stockholders' Equity [Abstract] 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. 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] 2022 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree 2023 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour 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. 2024 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive Forfeited, weighted average exercise price (in dollars per share) cabo_SharebasedCompensationArrangementsBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresInPeriodWeightedAverageExercisePrice Weighted average per share amount of forfeited share-based compensation awards. Thereafter us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive 2021 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo Other Noncurrent Liabilities [Table Text Block] Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Unrealized loss on cash flow hedges, gross 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). us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax Interest expense 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). Schedule of Intangible Assets and Goodwill [Table Text Block] Cash flows from financing activities: Total other noncurrent liabilities Other noncurrent liabilities us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Amount Interest rate swap liability Business Services [Member] Represents the information pertaining to business services. Accrued compensation and related benefits us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet Net assets acquired us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet Purchase price consideration Deferred revenue us-gaap_ContractWithCustomerLiabilityNoncurrent Contract with Customer, Liability, Noncurrent us-gaap_StockholdersEquity Total Stockholders' Equity Balance Balance us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities Total Liabilities Assumed us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired Purchase of business, net of cash acquired us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther Other noncurrent liabilities Class of Stock [Axis] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities Deferred income taxes Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue Deferred revenue, short-term portion us-gaap_PaymentsToAcquireBusinessesGross Payments to Acquire Businesses, Gross us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets Total Assets Acquired us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax Unrealized loss on cash flow hedges, net of tax Interest Rate Swap [Member] Derivative, Fixed Interest Rate Operating (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 Other receivables us-gaap_OtherReceivablesNetCurrent us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment Property, plant and equipment Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets Other noncurrent assets