Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements of Income
Operating revenues	$ 392,963	$ 393,413	$ 390,739
Operating expenses:
Cost of revenues (exclusive of depreciation and amortization)	165,835	162,474	166,280
Selling, general and administrative	118,420	123,798	115,974
Depreciation and amortization	89,916	87,879	78,014
Total operating expenses	374,171	374,151	360,268
Operating income	18,792	19,262	30,471
Other income (expense):
Interest expense	(17,095)	(16,786)	(16,496)
Interest income and other		(19)	34
Total other expense	(17,095)	(16,805)	(16,462)
Income before income tax provision	1,697	2,457	14,009
Income tax provision	591	1,357	5,910
Net income	$ 1,106	$ 1,100	$ 8,099
Net income per common share -
Basic (in dollars per share)	$ 0.10	$ 0.10	$ 0.76
Diluted (in dollars per share)	$ 0.10	$ 0.10	$ 0.72
Weighted average shares used to compute net income per common share -
Basic (in shares)	11,503,296	10,977,341	10,591,351
Diluted (in shares)	11,555,997	11,386,303	11,308,051