|**Tower Sale and Leaseback (Tables)**                                                                         | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                              
|------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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|**Tower Sale and Leaseback [Abstract]**                                                                       |                                                                                                                                                                                                                                                                                                                                                                             
|Tower Sale and Leaseback Balance Sheet Impacts                                                                | The following table summarizes the impacts to the Consolidated Balance Sheets (amounts in thousands):September 30, 2016Property and equipment(1)$19,159Tower obligation(2)$88,060(1)Property conveyed to VBT as part of the Tower Transaction, but remains on our Consolidated Balance Sheets.(2)Excluding current portion and net of deferred transaction costs.           
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|                                                                                                              |                                                                                                                                                                                                                                                                                                                                                                             
|                                                                                                              | September 30, 2016                                                                                                                                                                                                                                                                                                                                                          
|Property and equipment(1)                                                                                     | $                                                                                                                                                                                                                                                                                                                                                                           
|Tower obligation(2)                                                                                           | $                                                                                                                                                                                                                                                                                                                                                                           
|(1)Property conveyed to VBT as part of the Tower Transaction, but remains on our Consolidated Balance Sheets.
|(2)Excluding current portion and net of deferred transaction costs.                                          
|Furture minimum payments under Tower Obligation                                                               | Future minimum payments related to the Tower Obligation, including expected renewals and excluding deferred transaction costs, are summarized below (amounts in thousands):Years ending December 31,Total2016$1,73520176,99620187,13620197,27920207,4252021 and thereafter157,690Total minimum payments188,261Less amount representing interest98,118Tower obligation$90,143
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|                                                                                                              |                                                                                                                                                                                                                                                                                                                                                                             
|Years ending December 31,                                                                                     | Total                                                                                                                                                                                                                                                                                                                                                                       
|2016                                                                                                          | $                                                                                                                                                                                                                                                                                                                                                                           
|2017                                                                                                          | 6,996                                                                                                                                                                                                                                                                                                                                                                       
|2018                                                                                                          | 7,136                                                                                                                                                                                                                                                                                                                                                                       
|2019                                                                                                          | 7,279                                                                                                                                                                                                                                                                                                                                                                       
|2020                                                                                                          | 7,425                                                                                                                                                                                                                                                                                                                                                                       
|2021 and thereafter                                                                                           | 157,690                                                                                                                                                                                                                                                                                                                                                                     
|Total minimum payments                                                                                        | 188,261                                                                                                                                                                                                                                                                                                                                                                     
|Less amount representing interest                                                                             | 98,118                                                                                                                                                                                                                                                                                                                                                                      
|Tower obligation                                                                                              | $                                                                                                                                                                                                                                                                                                                                                                           

X- DefinitionTower Sale and Leaseback  [Abstract]
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duration X- DefinitionTabular disclosure of the aggregate amount of payments due on known contractual obligations for the five years following the date of the latest balance sheet and the combined aggregate amount of maturities of known contractual obligations.
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duration X- DefinitionTabular disclosure of leases entered into in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller was accounted for as an operating or capital lease. If the sale of the asset(s) did not meet the requirements to be accounted for as a sale whether the transaction was accounted for using the deposit method or as a financing.  Disclosure may also include a description of the terms of the sale-leaseback transaction, including future commitments, obligations, provisions, or circumstances that require or result in the seller-lessee's continuing involvement.  For leasing transactions involving "Special Purpose Entities"', disclosure may include a general description of the significant terms of the leasing arrangement including renewal or purchase options, escalation clauses, obligations with respect to refinancing of the lessor's debt, significant penalties and the provisions of any significant guarantees, such as residual value guarantees.
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