| **Industry Segments Data (Reportable segment) (Details) (USD $)In Thousands, unless otherwise specified** | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------|-----------------|
||
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | $ 811,648       | $ 710,181 | $ 679,381 |
| Cost of Goods Sold                                                                                        | 280,462         | 247,501 | 227,399 |
| Contribution                                                                                              | 531,186         | 462,680 | 451,982 |
| Less SG&A                                                                                             | 271,065         | 243,248 | 235,521 |
| Plus share-based compensation expense                                                                     | 6,638           | 5,040 | 6,620 |
| Plus non-cash contribution expense                                                                        | 0               | 960 | 0 |
| Plus (less) accretion expense                                                                             | 77              | 508 | 619 |
| Other expense                                                                                             | 447             | 869 | (59) |
| Adjusted EBITDA                                                                                           | 267,283         | 226,809 | 223,641 |
| Capital expenditures                                                                                      | 180,554         |   |   |
| Goodwill                                                                                                  | 219,041         | 77,294 | 74,883 |
| Total assets                                                                                              | 2,011,807       | 1,506,522 |   |
| Wholesale [Member]                                                                                        |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 197,218         | 124,745 | 119,521 |
| Consumer [Member]                                                                                         |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 274,805         | 269,357 | 266,750 |
| Business Services [Member]                                                                                |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 222,814         | 207,892 | 207,860 |
| Managed Broadband [Member]                                                                                |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 116,811         | 108,187 | 85,250 |
| Wireless [Member]                                                                                         |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     |            | 124,745 | 119,521 |
| Cost of Goods Sold                                                                                        | 68,086          | 58,737 | 42,687 |
| Contribution                                                                                              | 129,132         | 66,008 | 76,834 |
| Less SG&A                                                                                             | 20,030          | 15,475 | 14,868 |
| Plus share-based compensation expense                                                                     | 0               | 0 | 0 |
| Plus non-cash contribution expense                                                                        |            | 0 |   |
| Plus (less) accretion expense                                                                             | 507             | 269 | 349 |
| Other expense                                                                                             | 0               | 0 | 0 |
| Adjusted EBITDA                                                                                           | 109,609         | 50,802 | 62,315 |
| Capital expenditures                                                                                      | 28,156          |   |   |
| Goodwill                                                                                                  | 155,445         |   |   |
| Total assets                                                                                              | 624,740         |   |   |
| Wireless [Member] | Wholesale [Member]                                                                    |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 197,218         | 124,745 | 119,521 |
| Wireless [Member] | Consumer [Member]                                                                     |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 0               | 0 | 0 |
| Wireless [Member] | Business Services [Member]                                                            |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 0               | 0 | 0 |
| Wireless [Member] | Managed Broadband [Member]                                                            |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 0               | 0 | 0 |
| Wireline [Member]                                                                                         |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 614,430         | 585,436 | 559,860 |
| Cost of Goods Sold                                                                                        | 212,376         | 188,764 | 184,712 |
| Contribution                                                                                              | 402,054         | 396,672 | 375,148 |
| Less SG&A                                                                                             | 251,035         | 227,773 | 220,653 |
| Plus share-based compensation expense                                                                     | 6,638           | 5,040 | 6,620 |
| Plus non-cash contribution expense                                                                        |            | 960 |   |
| Plus (less) accretion expense                                                                             | (430)           | 239 | 270 |
| Other expense                                                                                             | 447             | 869 | (59) |
| Adjusted EBITDA                                                                                           | 157,674         | 176,007 | 161,326 |
| Capital expenditures                                                                                      | 152,398         |   |   |
| Goodwill                                                                                                  | 63,596          |   |   |
| Total assets                                                                                              | 1,387,067       |   |   |
| Wireline [Member] | Wholesale [Member]                                                                    |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 0               | 0 | 0 |
| Wireline [Member] | Consumer [Member]                                                                     |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 274,805         | 269,357 | 266,750 |
| Wireline [Member] | Business Services [Member]                                                            |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | 222,814         | 207,892 | 207,860 |
| Wireline [Member] | Managed Broadband [Member]                                                            |            |   |   |
| **Segment Reporting Information [Line Items]**                                                            |            |   |   |
| Total                                                                                                     | $ 116,811       | $ 108,187 | $ 85,250 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents Company's specificly defined non-GAAP measure - the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, accretion expense, non-cash contribution expense and noncontrolling interest.
+ References
No definition available.
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| X                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Capital Expenditures
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate cost of goods produced and sold and services rendered during the reporting period.
+ References
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+ Details**Name:**us-gaap_CostOfRevenue**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Noncash charitable contributions made by the entity during the period.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).
+ References
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| X                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.
+ References
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