Consolidated Statements Of Cash Flows (USD $)	6 Months Ended
	Jul. 02, 2011	Jul. 03, 2010
Cash flows from operating activities:
Net income	$ 94,598,000	$ 47,410,000
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	12,151,000	16,021,000
Equity-based compensation	8,013,000	5,155,000
Excess tax benefit from equity-based compensation	(1,234,000)	(16,000)
Loss (gain) on sale of fixed assets	5,000	(58,000)
Gain on sale of business	(68,001,000)	0
Deferred income taxes	3,899,000	2,961,000
Changes in assets and liabilities:
Accounts receivable, net	5,862,000	(1,956,000)
Inventories, net	(4,704,000)	(5,383,000)
Other assets	(2,319,000)	(8,664,000)
Accounts payable	(4,695,000)	6,672,000
Accrued liabilities	(13,614,000)	779,000
Deferred revenue	(14,738,000)	(337,000)
Income taxes	(4,333,000)	5,429,000
Other operating activities	(3,402,000)	(683,000)
Net cash provided by operating activities	7,488,000	67,330,000
Cash flows from investing activities:
Purchases of property and equipment	(11,232,000)	(15,053,000)
Payments for patents and licensing arrangements		(1,634,000)
Proceeds from the sale of business	161,008,000
Purchases of investments and marketable securities	(573,686,000)	(200,939,000)
Maturities of investments and marketable securities	351,722,000	149,929,000
Sales of investments and marketable securities	183,485,000	44,567,000
Net cash provided (used) by investing activities	111,297,000	(23,130,000)
Cash flows from financing activities:
Purchase of treasury stock	(82,388,000)	(46,767,000)
Proceeds from exercise of stock options and stock purchase plan purchases	8,096,000	5,033,000
Excess tax benefit from equity-based compensation	1,234,000	16,000
Net cash (used) in financing activities	(73,058,000)	(41,718,000)
Effect of exchange rate changes on cash	239,000	(143,000)
Net increase in cash and cash equivalents	45,966,000	2,339,000
Cash balance of discontinued operations at beginning of period	1,301,000	1,693,000
Cash balance of discontinued operations at end of period	(486,000)	(412,000)
Cash and cash equivalents at beginning of period	46,175,000	37,250,000
Cash and cash equivalents at end of period	92,956,000	40,870,000
Supplemental disclosures of cash flow information:
Income taxes paid	$ 52,819,000	$ 9,472,000