Commitments and Contingencies Restricted Cash (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014
Restricted Cash and Investments [Abstract]
Restricted cash	$ 1.2	$ 0.7
Claims reserve
Restricted Cash and Investments [Abstract]
Restricted cash	0.1
Restricted cash used	0.6
Other purposes
Restricted Cash and Investments [Abstract]
Restricted cash	0.7
Vermont | Broadband build-out
Restricted Cash and Investments [Abstract]
Restricted cash used	2.8
New Hampshire | Broadband build-out
Restricted Cash and Investments [Abstract]
Restricted cash	0.4
Restricted cash used	$ 2.9