Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Revenues:
Revenues before reimbursements	$ 108,467	$ 93,499	$ 330,514	$ 281,082
Reimbursements	7,938	5,164	22,249	15,579
Revenues	116,405	98,663	352,763	296,661
Operating expenses:
Compensation and related expenses	64,138	62,419	210,491	180,541
Other operating expenses	8,017	7,839	23,848	23,736
Reimbursable expenses	7,938	5,164	22,249	15,579
General and administrative expenses	4,193	2,834	10,626	11,290
Total operating expenses	84,286	78,256	267,214	231,146
Operating income	32,119	20,407	85,549	65,515
Other income, net:
Interest income, net	13	316	54	1,496
Miscellaneous income (expense), net	257	3,915	11,579	3,096
Total other income, net	270	4,231	11,633	4,592
Income before income taxes	32,389	24,638	97,182	70,107
Income taxes	7,815	6,554	16,360	9,395
Net income	$ 24,574	$ 18,084	$ 80,822	$ 60,712
Net income per share:
Basic (in dollars per share)	$ 0.47	$ 0.35	$ 1.54	$ 1.16
Diluted (in dollars per share)	$ 0.46	$ 0.34	$ 1.52	$ 1.14
Shares used in per share computations:
Basic (in shares)	52,618	52,316	52,597	52,383
Diluted (in shares)	53,312	53,209	53,316	53,342
Cash dividends declared per common share (in dollars per share)	$ 0.20	$ 0.19	$ 0.60	$ 0.57