Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 28, 2012	Dec. 30, 2011	Dec. 31, 2010
Revenues:
Revenues before reimbursements	$ 266,562	$ 246,667	$ 221,860
Reimbursements	26,091	25,779	26,893
Revenues	292,653	272,446	248,753
Operating expenses:
Compensation and related expenses	171,809	156,853	144,842
Other operating expenses	23,574	23,238	21,413
Reimbursable expenses	26,091	25,779	26,893
General and administrative expenses	13,559	13,116	12,364
Total operating expenses	235,033	218,986	205,512
Operating income	57,620	53,460	43,241
Other income:
Interest income, net	328	236	198
Miscellaneous income, net	3,801	1,123	3,269
Income before income taxes	61,749	54,819	46,708
Provision for income taxes	24,524	22,124	19,187
Net income	$ 37,225	$ 32,695	$ 27,521
Net income per share:
Basic	$ 2.70	$ 2.31	$ 1.92
Diluted	$ 2.60	$ 2.22	$ 1.83
Shares used in per share computations:
Basic	13,780	14,181	14,354
Diluted	14,293	14,751	15,069