Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Statement [Abstract]
Revenue	$ 424,415	$ 396,275	$ 331,407
Direct costs	333,086	311,984	260,172
Selling, general, and administrative expenses	66,867	64,981	57,305
Operating income	24,462	19,310	13,930
Interest and other income	1,424	231	102
Interest and other expense	441	418	263
Income before income taxes	25,445	19,123	13,769
Provision for income taxes	9,280	7,185	5,397
Net income	$ 16,165	$ 11,938	$ 8,372
Net income per share
Earnings per share, basic (in dollars per share)	$ 1.07	$ 0.80	$ 0.57
Earnings per share, diluted (in dollars per share)	$ 0.96	$ 0.71	$ 0.52
Weighted average shares outstanding
Basic (in shares)	15,172	14,968	14,697
Diluted (in shares)	16,841	16,731	16,073