Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016
Statement of Cash Flows [Abstract]
Cash and cash equivalents at beginning of period	$ 465,232	$ 616,686
Cash flows from operating activities:
Net income	218,543	164,609
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	86,605	89,726
Amortization of debt discount and fees	920	792
Stock-based compensation	94,008	79,986
Gain on investments, net	(12,502)	(4,070)
Gain on sale of property, plant and equipment	0	482
Deferred income taxes	212	8,657
Other non-cash items	3,763	1,869
Changes in operating assets and liabilities, net of effect of acquired businesses:
Receivables	(8,040)	2,873
Inventories	2,282	(16,339)
Prepaid expenses and other	(4,627)	(12,135)
Other assets	(14,469)	(3,822)
Accounts payable and accrued liabilities	(41,127)	(46,585)
Deferred revenue	14,245	(10,823)
Other long-term liabilities	4,071	(6,239)
Net cash provided by operating activities	343,884	248,017
Cash flows from investing activities:
Purchases of available-for-sale securities	0	(20,525)
Proceeds from the sale of available-for-sale securities	421	55,418
Proceeds from the maturity of available-for-sale securities	0	52,362
Proceeds from the sale of long-term investments	9,108	2,913
Proceeds from the sale of property, plant and equipment	0	482
Purchases of property, plant and equipment	(39,676)	(42,452)
Cash paid in business combinations and asset acquisitions, net of cash acquired	(550)	(41,627)
Net cash provided by (used for) investing activities	(30,697)	6,571
Cash flows from financing activities:
Proceeds from term loan	0	300,000
Proceeds from revolving credit facility	50,000	50,000
Payment on revolving credit facility	(100,000)	0
Payment of debt issuance costs	(793)	(622)
Proceeds from issuance of common stock	45,419	50,293
Stock received for payment of employee taxes on vesting of restricted stock	(54,130)	(35,532)
Payments for repurchases of common stock	(50,013)	(720,196)
Net cash used for financing activities	(109,517)	(356,057)
Effect of exchange rate changes on cash and cash equivalents	9,382	9,116
Increase (decrease) in cash and cash equivalents	213,052	(92,353)
Cash and cash equivalents at end of period	678,284	524,333
Supplemental cash flow information:
Cash paid for interest	14,188	11,238
Cash paid for taxes, net	$ 40,021	$ 27,332