Unaudited Condensed Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017
Cash flows from operating activities:
Net income	$ 9,510,000	$ 51,370,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	17,588,000	20,219,000
Purchase premium amortization/discount accretion on investments, net	(536,000)	102,000
Stock-based compensation	26,674,000	16,412,000
Impairment charges on investment	1,400,000	0
Deferred income taxes	(1,574,000)	(66,000)
Changes in assets and liabilities, net of effect of acquisitions:
Accounts receivable	60,148,000	18,248,000
Inventories	(86,230,000)	(1,216,000)
Prepaid expenses and other assets	(21,389,000)	5,557,000
Accounts payable	54,745,000	(20,016,000)
Accrued employee compensation	3,417,000	(12,595,000)
Other accrued liabilities	8,844,000	11,275,000
Deferred revenue	11,691,000	11,969,000
Income taxes payable	(10,432,000)	173,000
Net cash provided by operating activities	73,856,000	101,432,000
Cash flows from investing activities:
Purchases of short-term investments	(109,931,000)	(101,951,000)
Proceeds from maturities of short-term investments	102,054,000	101,544,000
Purchases of property and equipment	(19,883,000)	(9,805,000)
Proceeds from sale of investment	624,000	0
Purchases of investments	0	(2,900,000)
Payments made in connection with business acquisition, net of cash acquired	(14,352,000)	(737,000)
Net cash used in investing activities	(41,488,000)	(13,849,000)
Cash flows from financing activities:
Proceeds from Arlo initial public offering, net of offering costs	170,246,000	0
Repurchases of common stock	(15,000,000)	(86,630,000)
Restricted stock unit withholdings	(7,582,000)	(6,017,000)
Proceeds from exercise of stock options	5,184,000	6,405,000
Proceeds from issuance of common stock under employee stock purchase plan	5,554,000	4,764,000
Net cash provided by (used in) financing activities	158,402,000	(81,478,000)
Net increase in cash and cash equivalents	190,770,000	6,105,000
Cash and cash equivalents, at beginning of period	202,870,000	240,468,000
Cash and cash equivalents, at end of period	393,640,000	246,573,000
Non-cash investing and financing activities:
Additions to property and equipment included in accounts payable and other accrued liabilities	4,472,000	797,000
Estimated fair value of a facility under build-to-suit lease in other accrued liabilities	21,858,000	0
Estimated fair value of contingent consideration in connection with business acquisition in other accrued liabilities	$ 5,953,000	$ 0