Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]
Revenue	$ 130,538	$ 123,407	$ 250,743	$ 237,077
Operating expenses:
Cost of revenue (exclusive of depreciation and amortization included below)	89,871	84,253	172,951	166,135
Sales and marketing	9,764	9,123	19,684	18,272
General and administrative	20,373	19,188	40,719	38,669
Research and development	1,757	1,819	3,496	3,475
Depreciation and amortization	1,889	1,847	3,738	3,647
Amortization of acquisition-related intangible assets	813	828	1,611	1,656
Restructuring, impairment and other charges	882	1,297	1,216	2,021
Total operating expenses	125,349	118,355	243,415	233,875
Income from operations	5,189	5,052	7,328	3,202
Interest expense:
Interest on outstanding debt	100	210	249	447
Amortization of deferred financing charges	27	25	54	50
Interest income	31	13	50	39
Other expense (income), net	237	592	(111)	884
Income before income taxes	4,856	4,238	7,186	1,860
Provision for income taxes	1,066	771	1,514	1,363
Net income	$ 3,790	$ 3,467	$ 5,672	$ 497
Net income per share of common stock:
Basic	$ 0.06	$ 0.06	$ 0.09	$ 0.01
Diluted	$ 0.06	$ 0.06	$ 0.09	$ 0.01
Weighted average number of common shares outstanding:
Basic	60,523	60,724	60,372	60,550
Diluted	63,410	62,436	63,515	61,941