Retirement Plans - Narrative (Details) $ in Thousands	8 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) bond_fund	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	May 06, 2016 USD ($)
Ntelos Holding, Corp [Member]
Defined Benefit Plan Disclosure [Line Items]
Assumed annual rate increase in per capita cost of covered health care benefits				8.00%
Assumed annual rate decrease in per capita cost of covered health care benefits for the next five years		0.50%
Assumed annual rate per capita cost of covered health care benefits for year 2022 and thereafter				5.00%
Effect of one percentage point increase on service and interest cost components				$ 41
Effect of one percentage point increase on accumulated postretirement benefit obligation				800
Effect of one percentage point decrease on service and interest cost components				32
Effect of one percentage point decrease on accumulated postretirement benefit obligation				$ 634
Number of bond funds | bond_fund				2
Ntelos Holding, Corp [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Holding percentage of one asset in bond fund				4.00%
Holding percentage of one asset in total portfolio				1.00%
Pension Plan [Member] | Ntelos Holding, Corp [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations, at acquisition	$ 34,356			$ 34,356			$ 37,443
Net periodic cost (income)	(4,348)
Pension Plan [Member] | Ntelos Holding, Corp [Member] | Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)			$ (200)
Other Postretirement Benefit Plan [Member] | Ntelos Holding, Corp [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations, at acquisition	4,250			4,250			$ 4,298
Net periodic cost (income)	(48)
Other Postretirement Benefit Plan [Member] | Ntelos Holding, Corp [Member] | Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)			$ 200
401 (k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to plan				3,800	$ 2,600	$ 2,500
SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Liability due to participants	$ 2,900			$ 2,900	$ 2,700