CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Apr. 01, 2022
Cash flows from operating activities:
Net income	$ 2,710	$ 9,602
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation of property, plant, and equipment	1,113	994
Amortization of intangibles	7	8
Accretion/Amortization of investments available for sale	(983)
Deferred income taxes	57
Change in net pension liability	(13)	41
Stock-based compensation expense	6,065	3,894
Provision for sales returns and bad debts	(377)	(194)
Inventory provision	614	434
Changes in working capital:
Accounts receivable	(1,110)	(3,927)
Inventories	(3,920)	(1,483)
Prepayments, deposits, and other current assets	(4,249)	(4,505)
Accounts payable	(3,168)	2,668
Other current liabilities	(1,840)	(12,142)
Net cash used in operating activities	(5,094)	(4,610)
Cash flows from investing activities:
Acquisition of property and equipment	(2,901)	(2,539)
Purchase of investments available for sale	(27,445)
Proceeds from sale or maturity of investments available for sale	40,279
Net cash provided by (used in) investing activities	9,933	(2,539)
Cash flows from financing activities:
Repayment of finance lease obligations	(42)	(18)
Repurchase of employee common stock for taxes withheld	(1,849)
Proceeds from the exercise of stock options	529	912
Proceeds from vested restricted stock	1
Net cash provided by (used in) financing activities	(1,361)	894
Effect of exchange rate changes on cash and cash equivalents	10	(384)
Increase (decrease) in cash and cash equivalents	3,488	(6,639)
Cash and cash equivalents, at beginning of the period	86,480	199,706
Cash and cash equivalents, at end of the period	$ 89,968	$ 193,067