Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jul. 02, 2023	Jul. 03, 2022
Cash flows from operating activities:
Net income	$ 83,089	$ 126,234
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	29,153	28,053
Depreciation of property, plant, and equipment	8,177	8,114
(Gain) loss on disposal of property, plant, and equipment	(8)	12
Amortization of intangible assets	1,685	1,662
Excess and obsolete inventory charges	1,443	741
Non-cash impact of write-offs related to fire (Note 17)	0	44,903
Amortization of discounts or premiums on investments	1,200	2,714
Realized loss (gain) on sale of investments	0	24
Change in deferred income taxes	(14,158)	(10,809)
Accounts receivable	(24,420)	(44,118)
Unbilled revenue	(104)	1,704
Inventories	(4,981)	(20,122)
Prepaid expenses and other current assets	(5,289)	(45,752)
Accounts payable	(989)	(23,525)
Accrued expenses	(9,219)	(20,024)
Accrued income taxes	(13,684)	(372)
Deferred revenue and customer deposits	3,160	41,535
Other	2,347	2,655
Net cash provided by (used in) operating activities	57,402	93,629
Cash flows from investing activities:
Purchases of investments	(94,060)	(77,760)
Maturities and sales of investments	115,761	164,610
Purchases of property, plant, and equipment	(10,207)	(11,253)
Net cash provided by (used in) investing activities	11,494	75,597
Cash flows from financing activities:
Net payments from issuance of common stock under stock plans	2,655	4,414
Repurchase of common stock	(49,163)	(154,317)
Payment of dividends	(24,160)	(22,573)
Net cash provided by (used in) financing activities	(70,668)	(172,476)
Effect of foreign exchange rate changes on cash and cash equivalents	(2,117)	(5,865)
Net change in cash and cash equivalents	(3,889)	(9,115)
Cash and cash equivalents at beginning of period	181,374	186,161
Cash and cash equivalents at end of period	$ 177,485	$ 177,046