Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013
Cash flows from operating activities:
Net loss	$ (2,248)	$ (16,575)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	48,739	51,731
Stock-based compensation	16,334	19,461
Unrealized foreign exchange gain, net	(2,372)	(6,106)
Net amortization of premiums and accrued interest of investments	628	1,353
Asset impairments	770
Gain on investment securities and other	(86)	(1,767)
Excess tax benefits from stock option transactions		(2,274)
Changes in operating assets and liabilities:
Accounts receivable, net	(934)	1,923
Inventories, net	(3,514)	(7,110)
Prepaid expenses and other current assets	4,225	927
Accounts payable and accrued liabilities	(6,699)	(8,614)
Deferred taxes and income taxes payable	8,608	11,120
Deferred income	(1,980)	(915)
Net cash provided by operating activities	61,471	43,154
Cash flows from investing activities:
Cash paid in connection with business acquisition, net of cash acquired	(10,000)	(96,098)
Investment in long term deposits		(1,127)
Purchases of property and equipment	(11,175)	(11,297)
Purchase of intangible assets	(1,167)	(2,048)
Redemption of short-term investments	4,920	8,466
Sales of investment securities and other investments	37,936	146,340
Purchases of investment securities and other investments	(67,727)	(172,114)
Net cash used in investing activities	(47,213)	(127,878)
Cash flows from financing activities:
Proceeds from credit facility	30,000
Repayment of credit facility	(60,000)
Proceeds from issuance of common stock	17,924	23,476
Repurchases of common stock	(11,496)	(22,544)
Payment of debt issuance costs		(928)
Excess tax benefits from stock option transactions		2,274
Net cash (used in) provided by financing activities	(23,572)	2,278
Effect of exchange rate changes on cash and cash equivalents	(784)	(505)
Net decrease in cash and cash equivalents	(10,098)	(82,951)
Cash and cash equivalents, beginning of period	100,038	169,970
Cash and cash equivalents, end of period	89,940	87,019
Supplemental disclosures of cash flow information:
Cash paid for interest	276
Cash payments for income taxes, net	$ 747	$ 1,432