Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
	Oct. 02, 2011	Oct. 03, 2010
Cash flows from operating activities:
Net income	$ 68,533	$ 37,287
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	11,068	9,826
Purchase premium amortization on investments	467	90
Non-cash stock-based compensation	10,334	9,211
Income tax benefit associated with stock option exercises	3,269	1,996
Excess tax benefit from stock-based compensation	(3,426)	(2,112)
Deferred income taxes	(1,516)	(6,356)
Changes in assets and liabilities, net of effect of acquisitions:
Accounts receivable	8,078	(12,746)
Inventories	(2,279)	(19,804)
Prepaid expenses and other assets	(5,813)	30
Accounts payable	(13,484)	(29,179)
Accrued employee compensation	(940)	8,506
Other accrued liabilities	(3,013)	13,253
Deferred revenue	(3,604)	(1,149)
Income taxes payable	(4,521)	450
Net cash provided by operating activities	63,153	9,303
Cash flows from investing activities:
Purchases of short-term investments	(188,329)	(170,133)
Proceeds from sale of short-term investments	185,680	100,000
Purchase of property and equipment	(5,816)	(6,049)
Loan issued		(3,030)
Payments for patents		(1,270)
Payments made in connection with business acquisitions	(37,509)	(12,000)
Net cash used in investing activities	(45,974)	(92,482)
Cash flows from financing activities:
Purchase and retirement of treasury stock	(899)	(656)
Proceeds from exercise of stock options	26,647	6,867
Proceeds from issuance of common stock under employee stock purchase plan	1,752	1,202
Excess tax benefit from stock-based compensation	3,426	2,112
Net cash provided by financing activities	30,926	9,525
Net increase (decrease) in cash and cash equivalents	48,105	(73,654)
Cash and cash equivalents, at beginning of period	126,173	172,202
Cash and cash equivalents, at end of period	$ 174,278	$ 98,548