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Related party costs Related Party Costs Asset retirement obligations Asset Retirement Obligations, Noncurrent Customer relationships Customer Relationships [Member] Income from operations of discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Total operating expenses Costs and Expenses Equity Components [Axis] Equity Components [Axis] Unrealized income (loss) on interest rate hedge, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Minimum Minimum [Member] Top portion of peer percent group (as a percent) Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Comparison, Top Portion Of Peer Percent Group, Percentage Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Comparison, Top Portion Of Peer Percent Group, Percentage Balance Sheet Location [Domain] Balance Sheet Location [Domain] Land Land [Member] Current operating lease liabilities Operating Lease, Liability, Current Reconciliation of income from continuing operations from segments to consolidated [Abstract] Reconciliation of income from continuing operations from segments to consolidated [Abstract] Acquired subscribers - Cable Acquired Subscribers Cable [Member] Refers to acquired subscribers cable. 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Advanced billings and customer deposits Contract with Customer, Liability, Current Subsequent Event [Line Items] Subsequent Event [Line Items] Credit Facility [Domain] Credit Facility [Domain] Derivative Contract [Domain] Derivative Contract [Domain] Weighted average shares outstanding, diluted (in shares) Diluted weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Basic net income per share (in dollars per share) Increase (decrease) in earnings per share, basic (in dollars per share) Basic net income per share (in dollars per share) Earnings Per Share, Basic Selling, general and administrative Disposal Group, Including Discontinued Operation, Selling, General And Administrative Expense Disposal Group, Including Discontinued Operation, Selling, General And Administrative Expense Other income: Other Income and Expenses [Abstract] Entity File Number Entity File Number Debt Disclosure [Abstract] Debt Disclosure [Abstract] Benefit plan 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Sheet Location [Axis] Balance Sheet Location [Axis] Common stock, no par value, authorized 96,000; 49,852 and 49,671 issued and outstanding at September 30, 2020 and December 31, 2019, respectively Common Stock, Value, Issued Investments Long-term Investments Broadband contract acquisition and fulfillment costs Capitalized Contract Cost, Net, Noncurrent Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Document Fiscal Year Focus Document Fiscal Year Focus Rural local exchange carrier Carrier Access Revenue [Member] Carrier Access Revenue [Member] Total investments Other Long-term Investments Amortized and Capitalized Contract Cost Capitalized Contract Cost [Table Text Block] Current maturities of long-term debt, net of unamortized loan fees Long-term Debt, Current Maturities Entity Current Reporting Status Entity Current Reporting Status Inventory Disposal Group, Including Discontinued Operation, Inventory, Current 2024 Finance Lease, Liability, to be Paid, Year Four Valley Network Partnership Valley Network Partnership [Member] Valley Network Partnership [Member] Intangible assets, net and Goodwill Intangible Assets, Net (Including Goodwill) Other Liabilities Disclosure [Abstract] Other Liabilities Disclosure [Abstract] Subsequent Event [Table] Subsequent Event [Table] Stock-based compensation (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Restricted stock units granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Common stock, shares, issued (in shares) Common Stock, Shares, Issued Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value 2025 and thereafter Lessee, Lease Liability, Payments, Due After Year Four Lessee, Lease Liability, Payments, Due After Year Four Present value of lease liabilities Operating Lease, Liability Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Deferred tax liabilities, net Deferred Tax Liabilities, Net Long-term debt, less current maturities, net of unamortized loan fees Long-term Debt, Excluding Current Maturities Segment Reporting [Abstract] Segment Reporting [Abstract] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Debt Instrument [Line Items] Debt Instrument [Line Items] Total shareholders’ equity Balance Balance Stockholders' Equity Attributable to Parent Current liabilities held for sale Current liabilities held for sale Disposal Group, Including Discontinued Operation, Liabilities, Current Increase in assets Increase (Decrease) in Operating Assets Basis of Presentation and Other Information Nature of Operations [Text Block] Aggregate purchase price Business Combination, Consideration Transferred Total liabilities and shareholders’ equity Liabilities and Equity Principal payments on long-term debt Repayments of Other Long-term Debt Accumulated other comprehensive (loss) income, net of taxes Balance as of December 31, 2019 Balance as of September 30, 2020 Accumulated Other Comprehensive Income (Loss), Net of Tax Income Taxes Income Tax Disclosure [Text Block] Entity Address, City or Town Entity Address, City or Town Increase in liabilities Increase (Decrease) in Operating Liabilities Service revenue and other Service revenue and other Service and Other [Member] Service and Other [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Income from discontinued operations, net of tax Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax Operating lease, cost Operating Lease, Cost Hedging Relationship [Axis] Hedging Relationship [Axis] Current operating lease liabilities Disposal Group, Including Discontinued Operation, Operating Lease, Liability, Current Disposal Group, Including Discontinued Operation, Operating Lease, Liability, Current Total leverage ratio Leverage Ratio, Actual Represents actual leverage ratio. Anti-dilutive awards outstanding (fewer than) (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Relative Total Shareholder Return Awards (RTSRs) Relative Total Shareholder Return Awards [Member] Relative Total Shareholder Return Awards [Member] Finance lease, weighted average remaining lease term Finance Lease, Weighted Average Remaining Lease Term Cost of goods sold Product [Member] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Equity Component [Domain] Equity Component [Domain] Operating lease right-of-use assets Disposal Group, Including Discontinued Operation, Operating Lease, Right-Of-Use Asset, Current Disposal Group, Including Discontinued Operation, Operating Lease, Right-Of-Use Asset, Current LIABILITIES Liabilities [Abstract] Other assets Increase (Decrease) in Other Noncurrent Assets Property, plant and equipment, net Property, plant and equipment, net Property, Plant and Equipment, Net Entity Tax Identification Number Entity Tax Identification Number Non-current operating lease liabilities Disposal Group, Including Discontinued Operation, Operating Lease, Liability, Noncurrent Disposal Group, Including Discontinued Operation, Operating Lease, Liability, Noncurrent Earnings per Share & Stock Compensation Share-based Payment Arrangement [Text Block] Net Income Net income Net income Net Income (Loss) Attributable to Parent Non-current portion of financing leases Finance Lease, Liability, Noncurrent 2020 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Changes in assets and liabilities: Increase (Decrease) in Operating Assets [Abstract] London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Investment, Name [Domain] Investment, Name [Domain] Leases [Abstract] Leases [Abstract] Total current assets Assets, Current Current Fiscal Year End Date Current Fiscal Year End Date Corporate and Other Corporate and Other [Member] Operating expenses Operating Expenses [Abstract] Accrued liabilities and other Accrued Liabilities And Other [Member] Accrued Liabilities And Other [Member] Error Correction, Type [Axis] Error Correction, Type [Axis] Present value of lease liabilities Finance Lease, Liability Plant in service Other Plant in Service [Member] Amounts reclassified to interest expense Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Shareholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Stockholders' Equity Attributable to Parent [Abstract] 2025 and thereafter Finance Lease, Liability, To Be Paid, After Year Four Finance Lease, Liability, to be Paid, After Year Four Subscriber relationship acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Document Fiscal Period Focus Document Fiscal Period Focus 2021 Lessee, Lease Liability, Payments, Due Year One Lessee, Lease Liability, Payments, Due Year One Non-current portion of deferred lease revenue Contract with Customer, Liability, Noncurrent Less: Interest Lessee, Lease Liability, Undiscounted Excess Amount Lessee, Lease Liability, Undiscounted Excess Amount Percentage of patronage credit paid in share Percentage of Patronage Credit Paid in Share Represents the percentage of patronage credits paid in share by the entity. Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Equity method investments Equity Method Investment, Aggregate Cost Entity Filer Category Entity Filer Category Shares of Common Stock (no par value) Common Stock [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Product and Service [Domain] Product and Service [Domain] Long-Lived Tangible Asset [Domain] Long-Lived Tangible Asset [Domain] 2022 Lessee, Lease Liability, Payments, Due Year Two Lessee, Lease Liability, Payments, Due Year Two Broadband contract acquisition and fulfillment costs Capitalized Contract Cost, Net, Current Deferred charges and other assets Deferred charges and other assets Deferred Costs, Noncurrent Finance lease, weighted average discount rate, percent Finance Lease, Weighted Average Discount Rate, Percent Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Other Commitments [Axis] Other Commitments [Axis] Other Commitments [Domain] Other Commitments [Domain] 2021 Lessor, Operating Lease, Payment to be Received, Year One Net current period other comprehensive (loss) income Other Comprehensive Income (Loss), Tax Other Disposal Group, Including Discontinued Operation, Other Income Plant under construction Asset under Construction [Member] Gross Carrying Amount Finite-Lived Intangible Assets, Gross Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Bad debt expense Accounts Receivable, Credit Loss Expense (Reversal) Less: accumulated amortization and depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Installation and other Product and Service, Other [Member] Payments For Deposit On FCC Leases Payments For Deposit On FCC Leases Payments For Deposit On FCC Leases Stock options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Net increase in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Other income, net Other income, net Nonoperating Income (Expense) Hedging Relationship [Domain] Hedging Relationship [Domain] Error Corrections and Prior Period Adjustments Restatement [Line Items] Error Corrections and Prior Period Adjustments Restatement [Line Items] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Expected Maturity of Lease Liabilities, Operating Lessee, Operating Lease, Liability, Maturity [Table Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Other deferrals and accruals Increase (Decrease) in Other Accrued Liabilities Asset retirement obligations Disposal Group, Including Discontinued Operation, Asset Retirement Obligations, Noncurrent Disposal Group, Including Discontinued Operation, Asset Retirement Obligations, Noncurrent Weighted average shares outstanding, basic (in shares) Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Subsequent Events [Abstract] Subsequent Events [Abstract] Non-current assets held for sale Non-current assets held for sale Disposal Group, Including Discontinued Operation, Assets, Noncurrent Cash Flow Hedging Cash Flow Hedging [Member] Cash payments for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Ownership interest, percentage Equity Method Investment, Ownership Percentage Revenue from Contracts with Customers Revenue from Contract with Customer [Text Block] Right-of-use asset obtained in exchange for operating lease liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability 2020 Finance Lease, Liability, to be Paid, Remainder of Fiscal Year Additional paid in capital Additional Paid in Capital Income tax expense (benefit) Total income taxes for continuing operations Income Tax Expense (Benefit) Income taxes paid, net Income Taxes Paid, Net Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Title of Individual [Domain] Title of Individual [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Accrued liabilities and other Accrued liabilities and other Accrued Liabilities, Current Diluted net income per share (in dollars per share) Increase (decrease) in earnings per share, diluted (in dollars per share) Diluted net income per share (in dollars per share) Earnings Per Share, Diluted Local Phone Number Local Phone Number Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Intangible assets, net Disposal Group, Including Discontinued Operation, Intangible Assets, Current Total consolidated operating income (loss) Disposal Group, Including Discontinued Operation, Operating Income (Loss) Goodwill Disposal Group, Including Discontinued Operation, Goodwill, Current Derivative [Line Items] Derivative [Line Items] Intangible Assets Resulting from Acquisition Schedule of Indefinite-Lived Intangible Assets [Table Text Block] External revenue Entity Wide Information Revenue From External Customer [Abstract] Total Long-term Debt, Gross Long-term Debt Schedule of Long-term Debt Instruments [Table Text Block] Depreciation Depreciation Debt Service Coverage Ratio Minimum Debt Service Coverage Ratio Ratio of EBITDA divided by sum of all scheduled principal payments on Term Loans and regularly scheduled principal payments on other indebtedness plus cash interest. Entity Address, Address Line One Entity Address, Address Line One Entity Emerging Growth Company Entity Emerging Growth Company Stock options exercised Stock Issued During Period, Value, Stock Options Exercised Total indefinite-lived intangibles Indefinite-lived Intangible Assets (Excluding Goodwill) Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Award Type [Axis] Award Type [Axis] Revision of Prior Period, Error Correction, Adjustment Revision of Prior Period, Error Correction, Adjustment [Member] Prepaid expenses and other Prepaid Expenses and Other Current Assets [Member] Accumulated Amortization and Other Finite-Lived Intangible Assets, Accumulated Amortization Maximum Maximum [Member] Income before income taxes Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Net cash used in investing activities – discontinued operations Cash Provided by (Used in) Investing Activities, Discontinued Operations Retained Earnings Retained Earnings [Member] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] AOCI Attributable to Parent [Abstract] AOCI Attributable to Parent [Abstract] 2023 Lessor, Operating Lease, Payment to be Received, Year Three Current income taxes Increase (Decrease) in Income Taxes Receivable Award Type [Domain] Award Type [Domain] Minimum Rental Receipts Under Lease Agreement Lessor, Operating Leases Lessor, Operating Lease, Payment to be Received, Fiscal Year Maturity [Table Text Block] Investments [Domain] Investments [Domain] Trading Symbol Trading Symbol Revenue from related parties Revenue from Related Parties Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Retirement plan obligations Disposal Group, Including Discontinued Operation, Postretirement Plan Benefit Obligation, Current Discontinued Operations and Disposal Groups [Abstract] Net change in unrealized (loss) gain OCI, before Reclassifications, before Tax, Attributable to Parent Disposal Group Classification [Domain] Disposal Group Classification [Domain] Property, Plant and Equipment Property, Plant and Equipment Disclosure [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Shares issued (as a percent) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Issued In Period, Percentage Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Issued In Period, Percentage Current liabilities: Liabilities, Current [Abstract] Cash flows used in financing activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Entity Shell Company Entity Shell Company Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] 2022 Finance Lease, Liability, to be Paid, Year Two Adoption of New Accounting Policies New Accounting Pronouncements, Policy [Policy Text Block] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract]