Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net income	$ 1,810	$ 13,682
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	9,383	9,965
Stock-based compensation	15,508	13,197
Impairment of long-term investments	4,530	0
Deferred income taxes	2,867	2,116
Provision for excess and obsolete inventory	4,579	2,033
Other	89	(170)
Changes in assets and liabilities:
Accounts receivable	(323)	65,032
Inventories	80,325	(34,478)
Prepaid expenses and other assets	1,031	(4,812)
Accounts payable	(4,791)	(29,083)
Accrued employee compensation	2,769	(8,229)
Other accrued liabilities	(27,052)	(37,161)
Deferred revenue	2,281	182
Income taxes payable	(836)	(2,201)
Net cash provided by (used in) operating activities	92,170	(9,927)
Cash flows from investing activities:
Purchases of short-term investments	(147)	(149)
Proceeds from maturities of short-term investments	149	70,649
Purchases of property and equipment	(3,631)	(9,423)
Purchases of long-term investments	(6,265)	(5,200)
Net cash provided by (used in) investing activities	(9,894)	55,877
Cash flows from financing activities:
Repurchases of common stock	(22,508)	(31,980)
Restricted stock unit withholdings	(3,607)	(5,658)
Proceeds from exercise of stock options	3,786	2,949
Proceeds from issuance of common stock under employee stock purchase plan	2,478	2,303
Net cash used in financing activities	(19,851)	(32,386)
Net increase in cash and cash equivalents	62,425	13,564
Cash and cash equivalents, at beginning of period	190,208	201,047
Cash and cash equivalents, at end of period	$ 252,633	$ 214,611