| **Intangible Assets and Goodwill (Rollforward) (Details) - USD ($) $ in Thousands** | 12 Months Ended |
|-------------------------------------------------------------------------------------|-----------------|
||
| **Goodwill [Roll Forward]**                                                         |            |   |   |
| Goodwill beginning balance                                                          | $ 239,263       | $ 229,560 |   |
| Goodwill ending balance                                                             | 239,263         | 239,263 | $ 229,560 |
| **Finite-lived Intangible Assets [Roll Forward]**                                   |            |   |   |
| Beginning Balance                                                                   | 69,290          | 66,015 |   |
| Asset additions                                                                     | 17,601          | 15,023 |   |
| Software impairment                                                                 |            | (1,306) |   |
| Amortization expense                                                                | (12,447)        | (10,442) | (9,715) |
| Ending Balance                                                                      | 74,444          | 69,290 | 66,015 |
| Wireless                                                                            |            |   |   |
| **Goodwill [Roll Forward]**                                                         |            |   |   |
| Goodwill beginning balance                                                          | 164,312         | 164,312 |   |
| Goodwill ending balance                                                             | 164,312         | 164,312 | 164,312 |
| Wireline                                                                            |            |   |   |
| **Goodwill [Roll Forward]**                                                         |            |   |   |
| Goodwill beginning balance                                                          | 74,951          | 65,248 |   |
| Goodwill acquired during period                                                     |            | 9,703 |   |
| Goodwill ending balance                                                             | $ 74,951        | $ 74,951 | $ 65,248 |

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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
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| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                |
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| - Definition
Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.
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No definition available.
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| - 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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| - Definition
Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.
+ References
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| - Definition
The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.
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