Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Dec. 31, 2021
Revenues:
Revenues before reimbursements	$ 497,189	$ 463,820	$ 434,850
Reimbursements	39,577	49,473	31,419
Revenues	536,766	513,293	466,269
Operating expenses:
Compensation and related expenses	319,886	264,235	278,047
Other operating expenses	41,541	35,083	32,594
Reimbursable expenses	39,577	49,473	31,419
General and administrative expenses	24,440	23,660	15,282
Total operating expenses	425,444	372,451	357,342
Operating income	111,322	140,842	108,927
Other income:
Interest income	7,150	2,096	66
Miscellaneous income, net	17,424	(10,704)	16,844
Income before income taxes	135,896	132,234	125,837
Provision for income taxes	35,557	29,904	24,635
Net income	$ 100,339	$ 102,330	$ 101,202
Net income per share:
Basic (in dollars per share)	$ 1.96	$ 1.98	$ 1.92
Diluted (in dollars per share)	$ 1.94	$ 1.96	$ 1.9
Shares used in per share computations:
Basic (in shares)	51,152	51,727	52,610
Diluted (in shares)	51,635	52,280	53,331
Cash dividends declared per common share (in dollars per share)	$ 1.04	$ 0.96	$ 0.8