CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 11,111	$ 19,662
Adjustments to reconcile net income to net cash and cash equivalents provided by operating activities:
Amortization of intangibles	41,081	1,161
Depreciation	9,834	3,399
Foreign currency exchange loss (gain)	2,311	(774)
Share-based compensation	12,983	5,391
Acquired inventory step-up amortization	10,172
Provision for doubtful accounts and inventory valuation	5,437	1,921
Other, net	(1,765)	267
Changes in operating assets and liabilities	(18,305)	(6,127)
Net cash and cash equivalents provided by operating activities	72,859	24,900
Cash flows from investing activities:
Purchases of marketable securities	(250,928)	(52,945)
Proceeds from sales of marketable securities	201,764	62,231
Cash received from convertible note receivable	2,848
Purchases of property, plant and equipment	(3,391)	(4,201)
Net cash and cash equivalents (used in) provided by investing activities	(49,707)	5,085
Cash flows from financing activities:
Purchase of common stock	(52,000)	(744)
Tax payments related to shares withheld for share-based compensation plans	(3,546)	(750)
Payment of contingent consideration for acquired business	(435)	(1,121)
Issuance of shares through share-based compensation plans	2,845	283
Net cash and cash equivalents used in financing activities	(53,136)	(2,332)
Effect of exchange rate changes on cash and cash equivalents	917	(339)
Net (decrease) increase in cash and cash equivalents	(29,067)	27,314
Cash and cash equivalents at beginning of period	130,673	112,388
Cash and cash equivalents at end of period	101,606	139,702
Supplemental disclosure of cash flow information:
Income taxes paid (refunded)	$ 4,562	$ (4,067)