Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017
Cash Flows from Operating Activities
Net loss	$ (201,201)	$ (231,722)
Adjustments to reconcile net loss to net cash provided by operating activities:
Provision for doubtful accounts	37	7,805
Provision for inventory obsolescence	9,019	13,395
Depreciation	35,388	28,338
Write-off of property and equipment	7,513	5,250
Amortization of intangible assets	5,866	4,134
Stock-based compensation	73,613	67,256
Deferred income taxes	(1,690)	132,815
Impairment of equity investment	6,000	0
Other	(693)	1,301
Changes in operating assets and liabilities, net of acquisition:
Accounts receivable	80,227	208,899
Inventories	(80,064)	79,448
Prepaid expenses and other assets	123,356	(125,504)
Accounts payable	16,357	(122,160)
Accrued liabilities and other liabilities	(68,208)	(48,869)
Deferred revenue	(9,649)	(9,846)
Income taxes payable	5,653	(1,822)
Net cash provided by operating activities	1,524	8,718
Cash Flows from Investing Activities
Purchase of property and equipment	(40,174)	(58,199)
Purchases of marketable securities	(284,986)	(494,540)
Sales of marketable securities	93,020	19,806
Maturities of marketable securities	309,323	500,576
Acquisition, net of cash acquired	(13,646)	(556)
Net cash provided by (used in) investing activities	63,537	(32,913)
Cash Flows from Financing Activities
Repayment of debt	(747)	0
Proceeds from issuance of common stock	11,641	13,893
Taxes paid related to net share settlement of restricted stock units	(15,684)	(10,804)
Net cash (used in) provided by financing activities	(4,790)	3,089
Net increase (decrease) in cash and cash equivalents	60,271	(21,106)
Effect of exchange rate on cash and cash equivalents	0	467
Cash and cash equivalents at beginning of period	341,966	301,320
Cash and cash equivalents at end of period	$ 402,237	$ 280,681