Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net income	$ 13,833	$ 19,515
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	12,628	11,487
Amortization of deferred financing costs	194	194
Deferred income tax expense	7,726	12,226
Amortization of stock based compensation	2,816	2,200
Provision for doubtful accounts, service credits and other	875	1,337
Adjustment of non-cash transaction taxes	(259)	(354)
Loss/(Gain) on disposals of property and equipment	(2)	172
Changes in assets and liabilities:
Accounts receivable	(4,615)	3,129
Prepaid expenses and other assets	(240)	(285)
Accounts payable and accrued liabilities	(1,968)	(8,025)
Deferred revenue	1,264	(2,292)
Net cash provided by operating activities	32,252	39,304
Cash flows from investing activities:
Purchase of property and equipment	(6,327)	(7,772)
Proceeds from disposals of property and equipment	63	10
Net cash used in investing activities	(6,264)	(7,762)
Cash flows from financing activities:
Cash dividends to stockholders	(8,123)	(9,606)
Net cash used in financing activities	(8,123)	(9,606)
Net increase/(decrease) in cash and cash equivalents	17,865	21,936
Cash and cash equivalents, beginning of period	89,075	61,046
Cash and cash equivalents, end of period	106,940	82,982
Supplemental disclosure:
Interest paid	7	9
Income taxes paid	$ 1,327	$ 926