Note 5 - Revenue Streams and Concentrations - Revenue Streams (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017
Revenues		$ 16,252	[1]	$ 16,946	$ 49,867	[1]	$ 51,732
Sales Revenue, Services, Net [Member]
Revenues, percentage	[1]	100.00%			100.00%
Month-to-Month Customers [Member]
Revenues, within scope of ASU 2014-09		$ 7,492			$ 22,759
Revenues, percentage within scope of ASU 2014-09		62.10%			61.70%
Month-to-Month Customers [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage		46.10%
Month-to-Month Customers [Member] | Sales Revenue, Net [Member]
Revenues, percentage					45.60%
Competitive Local Exchange Carrier Business Customers [Member]
Revenues, within scope of ASU 2014-09		$ 3,447			$ 10,588
Revenues, percentage within scope of ASU 2014-09		28.60%			28.70%
Competitive Local Exchange Carrier Business Customers [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage		21.20%
Competitive Local Exchange Carrier Business Customers [Member] | Sales Revenue, Net [Member]
Revenues, percentage					21.20%
Network Access Customers [member]
Revenues, within scope of ASU 2014-09		$ 666			$ 2,076
Revenues, percentage within scope of ASU 2014-09		5.50%			5.60%
Network Access Customers [member] | Sales Revenue, Services, Net [Member]
Revenues, percentage		4.10%			4.20%
Month-to-Month, Competitive Local Exchange Carrier Business, and Network Access Customers [Member]
Revenues, within scope of ASU 2014-09		$ 11,605			$ 35,423
Revenues, percentage within scope of ASU 2014-09		96.20%			96.00%
Month-to-Month, Competitive Local Exchange Carrier Business, and Network Access Customers [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage		71.40%			71.00%
Global Access Customers [Member]
Revenues, within scope of ASU 2014-09	[2]	$ 464			$ 1,477
Revenues, percentage within scope of ASU 2014-09	[2]	3.80%			4.00%
Global Access Customers [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage	[2]	2.90%			3.00%
Month-to-Month, Competitive Local Exchange Carrier Business, Network Access, and Global Access Customers [Member]
Revenues, within scope of ASU 2014-09		$ 12,069			$ 36,900
Revenues, percentage within scope of ASU 2014-09		100.00%			100.00%
Month-to-Month, Competitive Local Exchange Carrier Business, Network Access, and Global Access Customers [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage		74.30%			74.00%
Sales Channel, Directly to Consumer [Member]
Revenues		$ 12,225			$ 37,390
Local services [Member]
Revenues		5,302			16,218
Local services [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		5,302			16,218
Network Access [Member]
Revenues		5,120			15,918
Network Access [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		1,131			3,553
Internet [Member]
Revenues		3,775			11,485
Internet [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		3,775			11,485
Transport Services [Member]
Revenues		1,211			3,613
Transport Services [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		1,173			3,500
Video and Security [Member]
Revenues		689			2,144
Video and Security [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		689			2,144
Management Service [Member]
Revenues		$ 155	[1]		$ 489
Management Service [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage	[1]	1.00%			1.00%
Management Service [Member] | Sales Channel, Directly to Consumer [Member]
Revenues		$ 155			$ 490
Indefeasible Rights-Of-Use Agreements, Outside of ASU 2014-09 Scope [Member]
Revenues	[1]	$ 38			$ 113
Indefeasible Rights-Of-Use Agreements, Outside of ASU 2014-09 Scope [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage	[1]	0.20%			0.20%
Network Access, Outside of ASU 2014-09 Scope [Member]
Revenues	[1]	$ 3,990			$ 12,364
Network Access, Outside of ASU 2014-09 Scope [Member] | Sales Revenue, Services, Net [Member]
Revenues, percentage	[1]	24.50%			24.80%

[1] Revenue generated from sources not within the scope of ASU 2014-09.

[2] Fixed fees charged to MTM customers and CLEC business customers.