CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Income Statement [Abstract]
Revenues	$ 590,901	$ 565,933	$ 508,373
Costs of services (exclusive of depreciation and amortization)	410,081	400,054	370,709
Selling, general and administrative expenses	110,087	97,372	90,028
Depreciation and amortization	11,996	12,768	12,840
Income from operations	58,737	55,739	34,796
Interest expense, net	(1,826)	(970)	(1,216)
Foreign currency gains (losses), net	1,889	(494)	42
Income before provision for income taxes	58,800	54,275	33,622
Provision for income taxes	15,181	12,596	9,115
Net income	$ 43,619	$ 41,679	$ 24,507
Net income per share:
Basic (in dollars per share)	$ 6.02	$ 5.59	$ 3.14
Diluted (in dollars per share)	$ 5.91	$ 5.45	$ 3.07
Weighted average number of shares outstanding:
Basic (in shares)	7,218	7,423	7,768
Diluted (in shares)	7,355	7,621	7,948