Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2017 USD ($) state segment	Sep. 30, 2013	Dec. 31, 2016 USD ($)	Sep. 14, 2016 USD ($)	Mar. 29, 2016 investigation
Revenues from External Customers and Long-Lived Assets [Line Items]
Recurring revenue billing period	1 month
Current customer deposits	$ 3,300,000		$ 3,300,000
Number of operating segments | segment	1
Number of operating states | state	17
MPUC
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of quarters consolidated into one		18 months
Number of Investigations | investigation					1
SQI regulatory examiners recommended penalty				$ 500,000
Other Accrued Liabilities
Revenues from External Customers and Long-Lived Assets [Line Items]
Deferred revenue	$ 19,500,000		18,200,000
Other Long Term Liabilities
Revenues from External Customers and Long-Lived Assets [Line Items]
Non-current deferred revenue	$ 4,800,000		$ 4,800,000
CAF Phase II
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue recognition period	6 years
Transition Funding
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue recognition period	3 years
Telephone Directories
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue recognition period	12 months