Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018
Cash flows from operating activities:
Net income	$ 13,682	$ 360
Net loss from discontinued operations	0	1,191
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	9,965	9,777
Purchase premium amortization/discount accretion on investments, net	(170)	(311)
Stock-based compensation	13,197	14,110
(Gains)/charges related to long-term investments, net	0	1,400
Deferred income taxes	2,116	3,437
Changes in assets and liabilities
Accounts receivable	65,032	27,634
Inventories	(32,445)	(7,312)
Prepaid expenses and other assets	(4,812)	(14,323)
Accounts payable	(29,083)	(8,784)
Accrued employee compensation	(8,229)	6,249
Other accrued liabilities	(37,161)	(6,980)
Deferred revenue	182	(528)
Income taxes payable	(2,201)	(5,000)
Net cash provided by (used in) continuing operating activities	(9,927)	20,920
Net cash provided by discontinued operating activities	0	19,147
Net cash provided by (used in) operating activities	(9,927)	40,067
Cash flows from investing activities:
Purchases of short-term investments	(149)	(70,017)
Proceeds from maturities of short-term investments	70,649	69,412
Purchases of property and equipment	(9,423)	(5,835)
Purchases of long-term investments	(5,200)	0
Net cash provided by (used in) continuing investing activities	55,877	(6,440)
Net cash used in discontinued investing activities	0	(7,533)
Net cash provided by (used in) investing activities	55,877	(13,973)
Cash flows from financing activities:
Repurchases of common stock	(31,980)	0
Restricted stock unit withholdings	(5,658)	(7,168)
Proceeds from exercise of stock options	2,949	2,869
Proceeds from issuance of common stock under employee stock purchase plan	2,303	2,732
Net cash used in continuing financing activities	(32,386)	(1,567)
Net cash used in financing activities	(32,386)	(1,567)
Net increase in cash and cash equivalents	13,564	24,527
Cash and cash equivalents, at beginning of period	201,047	202,870
Cash and cash equivalents, at end of period	214,611	227,397
Non-cash investing and financing activities:
Additions to property and equipment included in accounts payable and other accrued liabilities	$ 2,411	$ 292