| **Summary of Significant Accounting Principles (Property and Equipment) (Details) - USD ($) $ in Thousands** | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       |            | $ 1,337,122 |   |
| Property and equipment                                                                                       | $ 1,432,842     |   |   |
| Less accumulated depreciation                                                                                | 336,691         | 145,321 |   |
| Less accumulated depreciation on property and equipment under finance leases                                 | 5,250           | 7,195 |   |
| Property and equipment, net                                                                                  | 1,090,901       |   |   |
| Property and equipment, net                                                                                  | 1,090,901       | 1,184,606 |   |
| Depreciation expense                                                                                         | 204,200         | 153,500 | $ 200 |
| Capitalized interest costs                                                                                   | $ 4,200         | 3,900 |   |
| Land and buildings                                                                                           |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 25 years        |   |   |
| Property and equipment                                                                                       | $ 118,973       | 105,525 |   |
| Telephony transmission equipment and distribution facilities                                                 |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 837,966       | 763,957 |   |
| Telephony transmission equipment and distribution facilities | Minimum                                       |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 5 years         |   |   |
| Telephony transmission equipment and distribution facilities | Maximum                                       |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 20 years        |   |   |
| Cable transmission equipment and distribution facilities                                                     |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 120,642       | 100,391 |   |
| Cable transmission equipment and distribution facilities | Minimum                                           |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 5 years         |   |   |
| Cable transmission equipment and distribution facilities | Maximum                                           |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 30 years        |   |   |
| Support equipment and systems                                                                                |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 132,854       | 118,230 |   |
| Support equipment and systems | Minimum                                                                      |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 3 years         |   |   |
| Support equipment and systems | Maximum                                                                      |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 20 years        |   |   |
| Customer premise equipment                                                                                   |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 34,202        | 21,351 |   |
| Customer premise equipment | Minimum                                                                         |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 2 years         |   |   |
| Customer premise equipment | Maximum                                                                         |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 20 years        |   |   |
| Fiber optic cable systems                                                                                    |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 53,646        | 53,384 |   |
| Fiber optic cable systems | Minimum                                                                          |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 15 years        |   |   |
| Fiber optic cable systems | Maximum                                                                          |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 25 years        |   |   |
| Other                                                                                                        |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 21,478        | 19,381 |   |
| Other | Minimum                                                                                              |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 5 years         |   |   |
| Other | Maximum                                                                                              |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Useful lives                                                                                                 | 15 years        |   |   |
| Property and equipment under finance leases                                                                  |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment under finance leases                                                                  | $ 17,695        |   |   |
| Property and equipment under finance leases                                                                  |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment under finance leases                                                                  |            | 41,084 |   |
| Construction in progress                                                                                     |            |   |   |
| **Property, Plant and Equipment [Line Items]**                                                               |            |   |   |
| Property and equipment                                                                                       | $ 95,386        | $ 113,819 |   |

| X                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization
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Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, before Accumulated Depreciation and Amortization
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Cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land or leased assets).
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| - Definition
The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.
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| - Definition
Amount of interest capitalized during the period.
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| - Definition
Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.
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| - Definition
Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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