Acquisitions - Narrative (Details) customer in Thousands, $ in Thousands			3 Months Ended		6 Months Ended
	Apr. 06, 2017 USD ($) customer	May 06, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Business Acquisition [Line Items]
Acquisition related costs, legal services, professional services and severance accrualss				$ 14,800		$ 15,100
Integration and acquisition expenses			$ 3,678	20,054	$ 8,167	20,386
Amortization expense			200
Ntelos Holding, Corp
Business Acquisition [Line Items]
Aggregate purchase price		$ 667,800
Measurement period adjustment, amortization expense			100		100
Measurement period adjustment, depreciation expense				4,600		4,600
Integration and acquisition expenses			$ 5,400	$ 22,400	$ 12,500	$ 22,700
Term extend for affiliate relationship agreement		5 years
Limit of waived feed under affiliate agreement		$ 251,800
Period for additional waiver of management fee under affiliate agreement		6 months
Affiliate contract expansion | Ntelos Holding, Corp
Business Acquisition [Line Items]
Intangible asset useful life		14 years
Minimum | Ntelos Holding, Corp
Business Acquisition [Line Items]
Before amendment right or obligation to sell business		80.00%
Maximum | Ntelos Holding, Corp
Business Acquisition [Line Items]
After amendment right or obligation to sell business		90.00%
Management fee charge by Sprint		$ 4,200
Additional waiver of management fee under affiliate agreement		$ 5,000
Sprint and Affiliates | Sprint PCS Management Agreement, Former Retail, Post and Prepaid Subscribers, Sprint-branded Affiliate Customers
Business Acquisition [Line Items]
Number of customers | customer	25
Sprint and Affiliates | Spring PCS Management Agreement, Future Investment, Upgrade and Expand Existing Wireless Network Coverage
Business Acquisition [Line Items]
Future investment in existing wireless network	$ 32,000
Future investment in existing wireless network, term	3 years