CONSOLIDATED STATEMENTS OF NET INCOME AND COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Income Statement [Abstract]
Gross revenues	$ 786,778	$ 706,706	$ 659,296
Direct costs:
Salaries and wages	186,806	175,047	176,865
Sub-consultant services	153,641	124,998	107,602
Other direct costs	60,357	47,347	40,291
Total direct costs	400,804	347,392	324,758
Gross profit	385,974	359,314	334,538
Operating expenses:
Salaries and wages, payroll taxes, and benefits	193,488	176,838	176,816
General and administrative	66,114	53,986	50,214
Facilities and facilities related	21,252	20,193	21,280
Depreciation and amortization	38,938	39,953	42,079
Total operating expenses	319,792	290,970	290,389
Income from operations	66,182	68,344	44,149
Interest expense	(3,808)	(6,239)	(15,181)
Income before income tax expense	62,374	62,105	28,968
Income tax expense	(12,401)	(14,958)	(7,950)
Net income and comprehensive income	$ 49,973	$ 47,147	$ 21,018
Earnings per share:
Basic (in dollars per Share)	$ 3.39	$ 3.34	$ 1.70
Diluted (in dollars per Share)	$ 3.27	$ 3.22	$ 1.65
Weighted average common shares outstanding:
Basic (in shares)	14,753,738	14,135,333	12,362,786
Diluted (in shares)	15,260,186	14,656,381	12,713,075