Organization and Principles of Consolidation (Details) subscriptions in Thousands, mi in Thousands	Mar. 31, 2016 subscriptions States mi
Product Information [Line Items]
Number of operating states | States	17
Communication Services
Product Information [Line Items]
Number of route miles in fiber network, more than | mi	21
Number of data subscribers	311
Communication Services | Maine, New Hampshire and Vermont
Product Information [Line Items]
Number of route miles in fiber network, more than | mi	17
Ethernet Circuits
Product Information [Line Items]
Number of data subscribers	15
Residential Voice Lines
Product Information [Line Items]
Number of data subscribers	398,000