Earnings Per Share [Abstract] Earnings Per Share (EPS) Earnings Per Share [Text Block] Cover page. Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Statement of Financial Position [Abstract] Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current Inventory reserve Inventory Valuation Reserves Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Leases [Abstract] Leases Lessor, Operating Leases [Text Block] Leases Lessee, Operating Leases [Text Block] Leases Lessor, Sales-type Leases [Text Block] Leases Lessee, Finance Leases [Text Block] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts receivable, net of allowance for doubtful accounts of $516 and $534, respectively Accounts Receivable, Net, Current Income taxes receivable Income Taxes Receivable, Current Inventory, net of allowances of $69 and $113, respectively Inventory, Net Prepaid expenses and other Prepaid Expense and Other Assets, Current Total current assets Assets, Current Investments Long-term Investments Property, plant and equipment, net Property, Plant and Equipment, Net Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Goodwill Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Deferred charges and other assets Deferred Costs, Noncurrent Total assets Assets LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Current maturities of long-term debt, net of unamortized loan fees Long-term Debt, Current Maturities Accounts payable Accounts Payable, Current Advanced billings and customer deposits Contract with Customer, Liability, Current Accrued compensation Accrued Salaries, Current Current operating lease liabilities Operating Lease, Liability, Current Accrued liabilities and other Accrued Liabilities, Current Total current liabilities Liabilities, Current Long-term debt, less current maturities, net of unamortized loan fees Long-term Debt, Excluding Current Maturities Other Long-Term Liabilities Other Liabilities, Noncurrent [Abstract] Deferred income taxes Deferred Income Tax Liabilities, Net Deferred lease Deferred Rent Credit Asset retirement obligations Asset Retirement Obligations, Noncurrent Retirement plan obligations Liability, Defined Benefit Plan, Noncurrent Noncurrent operating lease liabilities Operating Lease, Liability, Noncurrent Other liabilities Other Liabilities, Noncurrent Total other long-term liabilities Liabilities, Other than Long-term Debt, Noncurrent Shareholders’ Equity Stockholders' Equity Attributable to Parent [Abstract] Common stock, no par value, authorized 96,000; 49,857 and 49,630 issued and outstanding at June 30, 2019 and December 31, 2018, respectively Common Stock, Value, Issued Additional paid in capital Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss), net of taxes Accumulated Other Comprehensive Income (Loss), Net of Tax Total shareholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and shareholders’ equity Liabilities and Equity Other Liabilities Disclosure [Abstract] Prepaid rent Prepaid Rent Prepaid maintenance expenses Prepaid Maintenance Expense, Current Prepaid Maintenance Expense, Current Interest rate swaps Derivative Asset, Current Contract asset Deferred Contract and Other Costs, Current Deferred Contract and Other Costs, Current Other Other Assets, Current Prepaid expenses and other Revenue from Contract with Customer [Abstract] Capitalized Contract Cost [Roll Forward] Capitalized Contract Cost [Roll Forward] Capitalized Contract Cost [Roll Forward] Beginning Balance Capitalized Contract Cost, Net Contract payments Capitalized Contract Cost, Payments Capitalized Contract Cost, Payments Contract amortization Capitalized Contract Cost, Amortization Ending Balance Contract Asset Balances and Activity Contract with Customer, Asset and Liability [Table Text Block] Revenue, Remaining Performance Obligation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Amortized and Capitalized Contract Costs Capitalized Contract Cost [Table Text Block] Contract Asset Balance [Roll Forward] Contract Asset Balance [Roll Forward] Contract Asset Balance [Roll Forward] Beginning balance Contract with Customer, Asset, Net Contract payments Contract with Customer, Assets, Payments Contract with Customer, Assets, Payments Contract amortization Contract with Customer, Reduction in Revenue, Amortization Contract with Customer, Reduction in Revenue, Amortization Ending balance 2019 Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year 2020 Lessor, Operating Lease, Payments to be Received, Two Years 2021 Lessor, Operating Lease, Payments to be Received, Three Years 2022 Lessor, Operating Lease, Payments to be Received, Four Years 2023 Lessor, Operating Lease, Payments to be Received, Five Years 2024 and thereafter Lessor, Operating Lease, Payments to be Received, Thereafter Total lease income Lessor, Operating Lease, Payments to be Received Commitments under leases under ASU 840, 2019 Operating Leases, Future Minimum Payments, Remainder of Fiscal Year Commitments under leases under ASU 840, 2020 Operating Leases, Future Minimum Payments, Due in Two Years Commitments under leases under ASU 840, 2021 Operating Leases, Future Minimum Payments, Due in Three Years Commitments under leases under ASU 840, 2022 Operating Leases, Future Minimum Payments, Due in Four Years Commitments under leases under ASU 840, 2023 Operating Leases, Future Minimum Payments, Due in Five Years Commitments under leases under ASU 840, thereafter Operating Leases, Future Minimum Payments, Due Thereafter Sales and property taxes payable Sales And Property Taxes Payable, Current Sales And Property Taxes Payable, Current Asset retirement obligations Asset Retirement Obligation, Current Accrued programming costs Accrued Programming Costs, Current Accrued Programming Costs, Current Financing leases Finance Lease, Liability, Current Other current liabilities Other Accrued Liabilities, Current Accrued liabilities and other Investments [Abstract] Investments Fair Value Disclosures [Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Shares of Common Stock (no par value) Common Stock [Member] Additional Paid in Capital Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance (in shares) Beginning balance Change in Accounting Principle - Adoption of ASU 2014-09 Cumulative Effect of New Accounting Principle in Period of Adoption Net income Net Income (Loss) Attributable to Parent Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Stock based compensation (in shares) Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Stock based compensation Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Stock options exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Stock options exercised Stock Issued During Period, Value, Stock Options Exercised Common stock issued Stock Issued During Period, Value, New Issues Shares retired for settlement of employee taxes upon issuance of vested equity awards (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Shares retired for settlement of employee taxes upon issuance of vested equity awards Adjustments Related to Tax Withholding for Share-based Compensation Common stock issued to acquire non-controlling interests of nTelos (in shares) Business Acquisition Noncontrolling Interest Issued Or Issuable Shares Assigned Number of shares (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity attributable to noncontrolling interests. Ending balance (in shares) Ending balance Debt Disclosure [Abstract] Long-Term Debt Debt Disclosure [Text Block] Awards excluded from the computation of diluted net income per share because their inclusion would have been anti-dilutive (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Effect of the Adoption of ASC Topic 842 (Leases) Accounting Standards Update 2016-02 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Assets Liabilities Liabilities [Abstract] Deferred Lease Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative [Table] Derivative [Table] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Not Designated as Hedging Instrument Not Designated as Hedging Instrument [Member] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash Flow Hedge Cash Flow Hedging [Member] Derivative [Line Items] Derivative [Line Items] Notional amount of cash flow hedges Derivative Asset, Notional Amount Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Term loan A-1 Term loan A-1 [Member] Loan from a bank/financial institution for a specific amount that has a specified repayment schedule and a fixed/floating interest rate. Term loan A-2 Term loan A-2 [Member] Loan from a bank/financial institution for a specific amount that has a specified repayment schedule and a fixed/floating interest rate. Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Total debt, net of unamortized loan fees Total debt, net of unamortized loan fees Amount after unamortized loan fees of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Unamortized loan fees Unamortized Loan Fees, Net Represents the net unamortized loan fees. Effective rate Debt Instrument, Interest Rate, Effective Percentage Variable interest rate Debt Instrument, Basis Spread on Variable Rate Periodic payment of principal Debt Instrument, Periodic Payment, Principal Periodic payment principal, period two Debt Instrument, Periodic Payment Principal, Period Two Amount of the required periodic payments applied to principal period two. Periodic payment principal, period three Debt Instrument, Periodic Payment Principal, Period Three Debt Instrument, Periodic Payment Principal, Period Three Additional payment to required quarterly payments Debt Instrument, Additional Payment To Required Quarterly Payments Debt Instrument, Additional Payment To Required Quarterly Payments Cash paid for interest, net of amounts capitalized Interest Paid, Excluding Capitalized Interest, Operating Activities Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Cable Cable [Member] The Cable segment provides video, internet and voice services in Virginia, West Virginia and Maryland. It includes the operations acquired from Jet Broadband, LLC, since July 30, 2010, and the operations acquired from Sudden link since November 30, 2010. Wireline Wireline [Member] The Wireline segment provides regulated and unregulated voice services, dial-up and DSL internet access, and long distance access services throughout Shenandoah County and portions of northwestern Augusta County, Virginia, and leases fiber optic facilities throughout the northern Shenandoah Valley of Virginia, northern Virginia and adjacent areas along the Interstate 81 corridor, including portions of West Virginia and Maryland. Management fee, percentage Management Fee, Percent Fee Postpaid wireless service fee as a deduction from gross revenues. Service fee retained by Sprint Net Service Fee, Percent Fee Post paid service fee percentage retained by Sprint. Management fee on prepaid wireless revenues and costs Management Fee Retained, Percent Fee Prepaid wireless service fee percentage retained by Sprint. Reimbursement payment, cost of equipment and commissions, benefit period for recognition Reimbursement Payment, Cost Of Equipment And Commissions, Benefit Period For Recognition Reimbursement Payment, Cost Of Equipment And Commissions, Benefit Period For Recognition Installation revenue, recognition period Revenue Recognition, Period Revenue Recognition, Period Commissions and other costs, recognition period (in months) Revenue, Commissions and Other Costs, Recognition Period Revenue, Commissions and Other Costs, Recognition Period Lease income from operating leases - fixed Sublease Income Operating lease expense Operating Lease, Cost Amortization of lease assets Finance Lease, Right-of-Use Asset, Amortization Interest on finance lease liabilities Finance Lease, Interest Expense Subtotal finance lease cost Finance Lease, Cost Finance Lease, Cost Total lease expense Lease, Cost Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest rate swap Interest Rate Swap [Member] Derivatives designated as hedging instruments Designated as Hedging Instrument [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Prepaid expenses and other Prepaid Expenses and Other Current Assets [Member] Deferred charges and other assets, net Deferred Charges and Other Assets, Net [Member] Line item in the statement of financial position in which the fair value amounts of the derivative instruments are included. Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract] Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract] Derivative assets Derivative Asset Total derivatives designated as hedging instruments Derivative Assets (Liabilities), at Fair Value, Net Derivatives and Hedging Derivative Instruments and Hedging Activities Disclosure [Text Block] Schedule of Other Current Assets Schedule of Other Current Assets [Table Text Block] Schedule of Other Assets, Noncurrent Schedule of Other Assets, Noncurrent [Table Text Block] Summary of Accrued Liabilities and Other Other Current Liabilities [Table Text Block] Summary of Other Liabilities Other Noncurrent Liabilities [Table Text Block] Statement of Cash Flows [Abstract] Cash Flows From Operating Activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Net income Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation Depreciation Amortization Amortization Reflected as Operating Expense The aggregate amount of recurring noncash operating expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives. Accretion of asset retirement obligations Asset Retirement Obligation, Accretion Expense Bad debt expense Provision for Doubtful Accounts Stock based compensation expense, net of amount capitalized Share-based Compensation Deferred income taxes Deferred Income Taxes and Tax Credits Net gain from patronage and investments Income (Loss) from Equity Method Investments Amortization of long-term debt issuance costs Amortization of Debt Issuance Costs Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Inventory, net Increase (Decrease) in Inventories Current income taxes Current Income Tax Expense (Benefit) Operating lease right-of-use assets Increase (Decrease) In Operating Lease, Right-Of Use Asset Increase (Decrease) In Operating Lease, Right-Of Use Asset Waived management fee Management Fee, Amount Waived Management Fee, Amount Waived Other assets Increase (Decrease) in Other Noncurrent Assets Accounts payable Increase (Decrease) in Accounts Payable Lease liabilities Increase (Decrease) In Lease Liability Increase (Decrease) In Lease Liability Deferred lease Increase (Decrease) in Deferred Liabilities Other deferrals and accruals Increase (Decrease) in Other Accrued Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Capital expenditures Payments to Acquire Property, Plant, and Equipment Cash disbursed for acquisitions Payments to Acquire Businesses, Gross Proceeds from sale of assets Proceeds from Sale of Machinery and Equipment Other Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows From Financing Activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Principal payments on long-term debt Repayments of Long-term Debt Proceeds from revolving credit facility borrowings Proceeds from Long-term Lines of Credit Principal payments on revolving credit facility Repayments of Long-term Lines of Credit Proceeds from exercises of stock options Proceeds from Stock Options Exercised Taxes paid for equity award issuances Payments Related to Tax Withholding for Share-based Compensation Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents, beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and cash equivalents, end of period Business Combinations [Abstract] Acquisition Business Combination Disclosure [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Schedule of other investments which do not have readily determinable fair values Schedule Of Other Investments Which Do Not Have Readily Determinable Fair Values [Table Text Block] Tabular disclosure of other investments which do not have readily determinable fair values. Property, Plant and Equipment [Abstract] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Investment [Table] Investment [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Domestic equity funds Domestic equity funds [Member] Equity securities issued by domestic or foreign corporate business, banks and other entities with a promise of repayment. International equity funds Foreign Corporate Equity Securities [Member] Foreign Corporate Equity Securities [Member] Investment [Axis] Investment [Axis] Investment [Domain] Investment [Domain] CoBank CoBank [Member] Equity securities investments. Other Other Equity Investments [Member] Equity securities investments. Investment [Line Items] Investment [Line Items] Total investments carried at fair value Equity Securities, FV-NI Total investments carried at cost Equity Securities, FV-NI, Cost Total equity method investments Equity Method Investment, Aggregate Cost Total investments Other Long-term Investments Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Amount paid to acquire indefinite-lived FCC spectrum licenses Asset Acquisition, Intangible Assets, Consideration Transferred Asset Acquisition, Intangible Assets, Consideration Transferred Amount paid at close to acquire indefinite-lived FCC spectrum licenses Asset Acquisition, Intangible Assets, Remaining Consideration Transferred Asset Acquisition, Intangible Assets, Remaining Consideration Transferred Remaining lease term (in years) Asset Acquisition, Remaining Lease Term Asset Acquisition, Remaining Lease Term Amount remitted to seller for purchase of indefinite-lived licenses Asset Acquisition, Amount Remitted To Seller Asset Acquisition, Amount Remitted To Seller Organization, Consolidation and Presentation of Financial Statements [Abstract] Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table] Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table] Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] Megahertz spectrum used Megahertz spectrum range used Radio frequencies used by the company. Initial term of contract Term of Contract Initial term of the contract. Number of contract renewals Number of Contract Renewals The number of times that a contract can be extended beyond its initial term. Length of renewals Length of Renewals Length of renewals after the initial term of a contract. Right or obligation to sell business, percentage of EBV Right or obligation to sell business The percentage of the Entire Business value the company has a right or obligation to sell business upon non-renewal, under the agreement. Other Assets and Accrued Liabilities Other Liabilities Disclosure [Text Block] Income Tax Disclosure [Abstract] Effective tax rate Effective Income Tax Rate Reconciliation, Percent Cash income taxes paid Income Taxes Paid Cash income tax refunds Proceeds from Income Tax Refunds Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Cable franchise rights Franchise Rights [Member] Railroad crossing rights Railroad Crossing Rights [Member] Railroad Crossing Rights [Member] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Sprint affiliate contract expansion - Wireless Affiliate Contract Expansion - Wireless [Member] Affiliate Contract Expansion - Wireless [Member] Favorable leases - Wireless Favorable Leases Wireless [Member] Refers to favorable leases wireless. Acquired subscribers - Cable Acquired Subscribers Cable [Member] Refers to acquired subscribers cable. Other intangibles Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Total non-amortizing intangibles Indefinite-lived Intangible Assets (Excluding Goodwill) Gross Carrying Amount Finite-Lived Intangible Assets, Gross Accumulated Amortization and Other Finite-Lived Intangible Assets, Accumulated Amortization Net Finite-Lived Intangible Assets, Net Total intangible assets, gross Intangible Assets, Gross (Excluding Goodwill) Total intangible assets, net Subscriber relationships acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Waived management fees under affiliate agreement Waived Management Fees Under Affiliate Agreement Waived Management Fees Under Affiliate Agreement Waived management fees under affiliate agreement, expected to be collected Waived Management Fees Under Affiliate Agreement, Amount Expected To Collect Waived Management Fees Under Affiliate Agreement, Amount Expected To Collect Subsequent Events Subsequent Events [Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Lease Income and Costs and Lease Terms and Discount Rates Lease, Cost [Table Text Block] Expected Maturity of Lease Liabilities, Operating Lessee, Operating Lease, Liability, Maturity [Table Text Block] Expected Maturity of Lease Liabilities, Financing Finance Lease, Liability, Maturity [Table Text Block] Minimum Rental Receipts Under Lease Agreement, Lessor, Operating Leases Lessor, Operating Lease, Payments to be Received, Maturity [Table Text Block] Schedule of Derivative Financial Instrument as Well as its Classification on the Consolidated Balance Sheet Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Adoption of New Accounting Principles Policy New Accounting Pronouncements, Policy [Policy Text Block] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Gains (Losses) on Cash Flow Hedges Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] AOCI Attributable to Parent [Abstract] AOCI Attributable to Parent [Abstract] Gains (Losses) on Cash Flow Hedges AOCI Attributable to Parent, Before Tax [Roll Forward] AOCI Attributable to Parent, Before Tax [Roll Forward] Balance as of December 31, 2018 AOCI before Tax, Attributable to Parent Net change in unrealized gain (loss) Other Comprehensive Income (Loss), before Reclassifications, before Tax Amounts reclassified from accumulated other comprehensive income to interest expense Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Net current period accumulated other comprehensive income (loss) Other Comprehensive Income (Loss), before Tax Balance as of June 30, 2019 Income Tax Expense AOCI Attributable to Parent, Tax [Roll Forward] AOCI Attributable to Parent, Tax [Roll Forward] Balance as of December 31, 2018 AOCI Tax, Attributable to Parent Net change in unrealized gain (loss) Other Comprehensive Income (Loss) before Reclassifications, Tax Amounts reclassified from accumulated other comprehensive income to interest expense Reclassification from AOCI, Current Period, Tax Net current period accumulated other comprehensive income (loss) Other Comprehensive Income (Loss), Tax Balance as of June 30, 2019 Accumulated Other Comprehensive Income (Loss), net of taxes AOCI Attributable to Parent, Net of Tax [Roll Forward] Balance as of December 31, 2018 Net change in unrealized gain (loss) Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Amounts reclassified from accumulated other comprehensive income to interest expense Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Net current period accumulated other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Balance as of June 30, 2019 Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land Land [Member] Buildings and structures Building and Building Improvements [Member] Cable and fiber Other Machinery and Equipment [Member] Equipment and software Equipment and Software [Member] Purchased software applications and internally developed software for sale, licensing or long-term internal use and related equipment. Plant in service Other Plant in Service [Member] Plant under construction Asset under Construction [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Useful life (in years) Property, Plant and Equipment, Useful Life Property, plant and equipment [Abstract] Property, Plant and Equipment, Net, by Type [Abstract] Total property, plant and equipment Property, Plant and Equipment, Gross Less accumulated amortization and depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, plant and equipment, net Leverage ratio, actual Leverage Ratio, Actual Represents actual leverage ratio. Covenant requirement, total leverage ratio Ratio of Indebtedness to EBITDA Ratio of indebtedness to earnings before interest, taxes, depreciation and amortization. Debt service coverage ratio, actual Debt Service Coverage Ratio, Actual Represents actual debt service coverage ratio. Minimum 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. Covenant, liquidity balance, actual Debt Instrument, Covenant, Liquidity Balance, Actual Debt Instrument, Covenant, Liquidity Balance, Actual Debt instrument covenants minimum liquidity amount Debt Instrument Covenants Minimum Liquidity Amount Represents the minimum liquidity balance, defined as availability under the revolver facility plus unrestricted cash and cash equivalents on deposit in a deposit account for which a control agreement has been delivered to the administrative agent. Segment Reporting [Abstract] Selected Financial Data for Segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Non-current portion of deferred revenues Contract with Customer, Liability, Noncurrent Noncurrent portion of financing leases Finance Lease, Liability, Noncurrent Other Other Accrued Liabilities, Noncurrent Other liabilities Long-term debt Long-term Debt Less: unamortized loan fees Total debt, net of unamortized loan fees Current maturities of long-term debt, net of current unamortized loan fees Current maturities, net of unamortized loan fees Amount, after unamortized loan fees classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Long-term debt, less current maturities, net of unamortized loan fees Long-term debt, net of unamortized loan fees Amount after unamortized loan fees of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Customer Concentration Collaborative Arrangement Disclosure [Text Block] Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Operating Leases Operating Lease Liabilities, Payments Due [Abstract] 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five 2024 and thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total lease payments Lessee, Operating Lease, Liability, Payments, Due Less: Interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Present value of lease liabilities Operating Lease, Liability Finance Leases Finance Lease Liabilities, Payments, Due [Abstract] 2019 Finance Lease, Liability, Payments, Remainder of Fiscal Year 2020 Finance Lease, Liability, Payments, Due Year Two 2021 Finance Lease, Liability, Payments, Due Year Three 2022 Finance Lease, Liability, Payments, Due Year Four 2023 Finance Lease, Liability, Payments, Due Year Five 2024 and thereafter Finance Lease, Liability, Payments, Due after Year Five Total lease payments Finance Lease, Liability, Payments, Due Less: Interest Finance Lease, Liability, Undiscounted Excess Amount Present value of lease liabilities Finance Lease, Liability Total Lease Liabilities, Payments, Due [Abstract] Lease Liabilities, Payments, Due [Abstract] 2019 Lessee, Lease Liability, Payments, Remainder of Fiscal Year Lessee, Lease Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Lease Liability, Payments, Due Year Two Lessee, Lease Liability, Payments, Due Year Two 2021 Lessee, Lease Liability, Payments, Due Year Three Lessee, Lease Liability, Payments, Due Year Three 2022 Lessee, Lease Liability, Payments, Due Year Four Lessee, Lease Liability, Payments, Due Year Four 2023 Lessee, Lease Liability, Payments, Due Year Five Lessee, Lease Liability, Payments, Due Year Five 2024 and thereafter Lessee, Lease Liability, Payments, Due After Year Five Lessee, Lease Liability, Payments, Due After Year Five Total lease payments Lessee, Lease Liability, Payments, Due Lessee, Lease Liability, Payments, Due Less: Interest Lessee, Lease Liability, Undiscounted Excess Amount Lessee, Lease Liability, Undiscounted Excess Amount Present value of lease liabilities Lease, Liability Lease, Liability Interest rate swaps Contract asset Deferred Contract and Other Costs, Non-Current Deferred Contract and Other Costs, Non-Current Other Other Assets, Noncurrent Deferred charges and other assets Revenue from Contracts with Customers Revenue from Contract with Customer [Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Wireless Wireless [Member] The Wireless segment provides digital wireless service to a portion of a four-state area covering the region from Harrisburg, York and Altoona, Pennsylvania, to Harrisonburg, Virginia, as a Sprint PCS Affiliate of Sprint Nextel. This segment also owns cell site towers built on leased land, and leases space on these towers to both affiliates and non-affiliated service providers. Goodwill [Line Items] Goodwill [Line Items] Schedule of long term debt Schedule of Long-term Debt Instruments [Table Text Block] Financial covenants in credit agreements Financial Covenants In Credit Agreements [Table Text Block] Tabular disclosure of financial covenants in credit agreements. Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Subscriber Relationships Customer Relationships [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Big Sandy Acquisition Big Sandy Acquisition [Member] Big Sandy Acquisition [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Cash purchase price Business Combination, Consideration Transferred Property, plant and equipment acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Goodwill acquired Estimated useful life, acquired property, plant and equipment Estimated useful life, acquired intangible asset Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Segment Reporting Segment Reporting Disclosure [Text Block] Weighted-average remaining lease term (years) Weighted-Average Remaining Lease Term [Abstract] Weighted-Average Remaining Lease Term [Abstract] Operating leases Operating Lease, Weighted Average Remaining Lease Term Finance leases Finance Lease, Weighted Average Remaining Lease Term Weighted-average discount rate Weighted-Average Discount Rate [Abstract] Weighted-Average Discount Rate [Abstract] Operating leases Operating Lease, Weighted Average Discount Rate, Percent Finance leases Finance Lease, Weighted Average Discount Rate, Percent Income Taxes Income Tax Disclosure [Text Block] Operating cash flows used by leases Operating Lease, Payments Leased assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Service revenue Services Revenue [Member] Services Revenue [Member] Equipment revenue Equipment Revenue [Member] Equipment Revenue [Member] Tower revenue Tower Revenue [Member] Tower Revenue [Member] Other revenue Other Revenue [Member] Other Revenue [Member] Cost of services Service [Member] Cost of goods sold Product [Member] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Intersegment Eliminations Intersegment Eliminations [Member] Operating Segments Operating Segments [Member] Wireless Other Other Segments [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract] Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract] External revenue External revenues [Abstract] Operating revenues Revenue from Contract with Customer, Excluding Assessed Tax Operating expenses: Operating Expenses [Abstract] Cost of services Cost of Goods and Services Sold Selling, general and administrative Selling, General and Administrative Expense Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Total operating expenses Operating Expenses Operating income Operating Income (Loss) Property, Plant and Equipment Property, Plant and Equipment Disclosure [Text Block] Calculation of net income per share: Earnings Per Share, Basic [Abstract] Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Basic income per share (in dollars per share) Earnings Per Share, Basic Effect of stock options outstanding: Dilutive Securities, Effect on Basic Earnings Per Share [Abstract] Effect from dilutive shares and options outstanding (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Diluted weighted average shares (in shares) Weighted Average Number of Shares Outstanding, Diluted Diluted income per share (in dollars per share) Earnings Per Share, Diluted Remaining performance obligations Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Remaining performance obligations, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Changes in Carrying Amount of Goodwill Schedule of Goodwill [Table Text Block] Schedule of Intangible Assets Schedule of Intangible Assets and Goodwill [Table Text Block] Income Statement [Abstract] Service revenue and other Service Revenue and Other [Member] Service Revenue and Other [Member] Equipment revenue Statement [Line Items] Operating revenue: Revenues [Abstract] Depreciation and amortization Other income (expense): Other Income and Expenses [Abstract] Interest expense Interest Expense Other Other Nonoperating Income (Expense) Income before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) Net income Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Unrealized gain (loss) on interest rate hedge, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Unrealized gain (loss) on interest rate hedge, net of tax Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Net income per share, basic and diluted: Earnings Per Share, Basic and Diluted [Abstract] Basic net income per share (in dollars per share) Diluted net income per share (in dollars per share) Weighted average shares outstanding, basic (in shares) Weighted average shares outstanding, diluted (in shares)