Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Oct. 01, 2021
Cash flows from operating activities:
Net income	$ 79,806	$ 80,822
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and leasehold improvements	5,224	4,943
Amortization of premiums and accretion of discounts on short-term investments		(11)
Provision for contract losses and doubtful accounts	2,112	1,197
Stock-based compensation	16,072	15,239
Deferred income tax provision	(3,955)	(2,020)
Changes in operating assets and liabilities:
Accounts receivable	(28,265)	(33,671)
Prepaid expenses and other current assets	(7,583)	(4,878)
Change in operating leases	(132)	(472)
Accounts payable and accrued liabilities	5,140	5,784
Accrued payroll and employee benefits	(11,211)	3,053
Deferred revenues	(3,971)	392
Net cash provided by operating activities	53,237	70,378
Cash flows from investing activities:
Capital expenditures	(9,108)	(5,437)
Purchase of short-term investments		(34,994)
Maturity of short-term investments		55,000
Net cash provided by (used in) investing activities	(9,108)	14,569
Cash flows from financing activities:
Payroll taxes for restricted stock units	(12,904)	(15,666)
Repurchase of common stock	(142,195)	(7,000)
Exercise of stock-based payment awards	1,627	2,675
Dividends and dividend equivalents rights	(37,084)	(32,775)
Net cash used in financing activities	(190,556)	(52,766)
Effect of foreign currency exchange rates on cash and cash equivalents	(2,817)	79
Net decrease in cash and cash equivalents	(149,244)	32,260
Cash and cash equivalents at beginning of period	297,687	197,525
Cash and cash equivalents at end of period	$ 148,443	$ 229,785