Consolidated Statements of Income (Unaudited) (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Income [Abstract]
Revenue	$ 161,203	$ 126,558	$ 311,428	$ 241,550
Operating costs and expenses:
Cost of revenue	145,670	110,927	278,926	210,318
General and administrative expense	6,085	5,369	11,844	10,985
Depreciation and amortization	1,817	1,193	3,125	2,366
Acquisition and integration related expenses	748		949
Total operating costs and expenses	154,320	117,489	294,844	223,669
Operating income	6,883	9,069	16,584	17,881
Interest expense, net	483	149	680	292
Income before income taxes	6,400	8,920	15,904	17,589
Provision for income taxes	2,542	3,524	6,353	6,727
Net income	$ 3,858	$ 5,396	$ 9,551	$ 10,862
Basic:
Weighted average shares outstanding	13,681	13,628	13,675	13,598
Net income per share	$ 0.28	$ 0.40	$ 0.70	$ 0.80
Diluted:
Weighted average shares and equivalent shares outstanding	13,931	13,886	13,919	13,882
Net income per share	$ 0.28	$ 0.39	$ 0.69	$ 0.78