Summary of Significant Accounting Policies - Benefit Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of projected benefit obligations	$ 12,675	$ 11,519
nTelos Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of projected benefit obligations	6,824	5,131
OPEB Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of projected benefit obligations	3,573	3,193
SERP Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of projected benefit obligations	$ 2,278	$ 3,195