Accounts Payable and Accrued Liabilities - Components of Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accounts payable	$ 1,578	$ 2,784
Accrued network costs	1,021	1,072
Accrued taxes	4,225	4,195
Asset retirement obligations	327	342
Accrued outside services	959	1,101
Accrued accounting and legal	322	275
Accrued recognition awards	340	345
Accrued other	430	696
Deferred rent	76	77
Escheat liability	12	0
Lease incentive	40	147
Dividends payable - 2011 LTIP	0	637
Capital lease payable	10	17
Total accounts payable and accrued liabilities	9,340	$ 11,688
Decrease in accounts payable	$ 1,200