Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019
Cash flows from operating activities:
Net income	$ 133,733	$ 65,259
Adjustments to reconcile net income to net cash provided by (used in) operating activities, net of the effects of acquisition:
Depreciation and amortization	25,705	27,744
Debt and Equity Securities, Unrealized Gain (Loss)	(43,480)	0
Stock-based compensation	20,904	18,742
Deferred income taxes, net	10,939	(5,873)
Other	4,785	4,687
Changes in operating assets and liabilities — (use) source
Accounts receivable	(32,572)	(10,948)
Inventory	(61,006)	(83,863)
Other assets	(20,718)	(8,155)
Accounts payable	46,098	(27,256)
Accrued expenses and other liabilities	12,358	(11,916)
Net cash provided by (used in) operating activities	96,746	(31,579)
Cash flows from investing activities:
Additions of property and equipment	(25,031)	(27,080)
Change in other assets	(3,729)	(5,336)
Cash paid for business acquisition, net of cash acquired	0	(2,817)
Sales and maturities of investments	10,500	9,380
Net cash used in investing activities	(18,260)	(25,853)
Cash flows from financing activities:
Proceeds from employee stock plans	4,048	4,981
Income tax withholding payment associated with restricted stock vesting	(1,845)	(7,277)
Stock repurchases	25,000	0
Net cash used in financing activities	(22,797)	(2,296)
Effect of exchange rate changes on cash and cash equivalents	2,125	(103)
Net increase (decrease) in cash and cash equivalents	57,814	(59,831)
Cash and cash equivalents, at beginning of period	239,392	130,373
Cash and cash equivalents, at end of period	$ 297,206	$ 70,542