Accounts Payable and Accrued Liabilities - Components of Accounts Payable and Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Payables and Accruals [Abstract]
Accounts payable	$ 1,637	$ 2,205
Accrued network costs	1,338	1,388
Accrued taxes	4,289	4,171
Asset retirement obligations	663	379
Accrued outside services	1,042	869
Accrued accounting and legal	447	653
Accrued recognition awards	241	294
Accrued other	789	852
Deferred rent	77	88
Escheat liability	25	78
Lease incentive	142	87
Dividends payable for LTIP and to Board of Directors	5	1,484
Royalty payable	110	111
Total accounts payable and accrued liabilities	$ 10,805	$ 12,659