| **Segments (Tables)**                                                       | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Segment Reporting [Abstract]**                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Schedule of Segment Profitability Definition Adjustments [Table Text Block] | The effect of removing the Roaming Adjustment from Adjusted EBITDA for the three months ended March 31, 2016 and the three and six months ended June 30, 2016 follows (amounts in thousands): Wireless Segment Adjusted EBITDA Adjusted EBITDA as Previously DefinedRemoval of Roaming AdjustmentAdjusted EBITDAFirst Quarter 2016$40,064(7,500)32,564Second Quarter 2016$40,334(7,500)32,834Six Months Ended June 30, 2016$80,398(15,000)65,398                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Schedule of Segment Reporting Information, by Segment                       | Summarized financial information for our reportable segments for the three and nine months ended September 30, 2016 and 2015 follows (amounts in thousands): Three Months Ended Nine Months Ended Wireless Wireline Total Reportable Segments Wireless Wireline Total Reportable SegmentsSeptember 30, 2016           Revenues$52,327 184,328 236,655 $157,664 543,855 701,519Adjusted EBITDA$32,018 46,167 78,185 $97,416 122,915 220,331            September 30, 2015           Revenues$80,424 178,149 258,573 $207,568 529,622 737,190Adjusted EBITDA$57,404 39,122 96,526 $140,518 119,312 259,830                                                                                                           |
| Reconciliation of Total EBITDA to Operating Profit (Loss)                   | A reconciliation of reportable segment Adjusted EBITDA to consolidated income (loss) before income taxes follows (amounts in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015Reportable segment Adjusted EBITDA$78,185 96,526 220,331 259,830Less depreciation and amortization expense(47,819) (45,157) (143,033) (135,563)Less share-based compensation expense(2,810) (2,660) (7,820) (8,074)Less imputed interest on financed devices(651) (268) (1,885) (438)Less accretion expense(406) (191) (1,240) (992)Less software impairment charge— (2,571) — (29,839)Other(131) (206) (435) 493Consolidated operating income26,368 45,473 65,918 85,417Less other expense, net(16,134) (19,856) (46,215) (107,361)Consolidated income (loss) before income taxes$10,234 25,617 19,703 (21,944) |

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| - Definition
Reconciliation of Total adjusted EBITDA to Consolidated income (loss) before income taxes. [Table Text Block]
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No definition available.
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Schedule of Segment Profitability Definition Adjustments [Table Text Block]
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No definition available.
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Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.
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