Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 29, 2012	Jan. 30, 2011	Jan. 31, 2010
Cash flows from operating activities:
Net income	$ 89,087	$ 72,572	$ 957
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	18,543	16,448	8,357
Deferred income taxes	(2,023)	3,184	17,427
Impairment of acquired intangible assets	2,470
Stock-based compensation	24,020	29,010	19,935
Excess tax benefits on stock based compensation	(2,279)	(891)	(493)
Loss (Gain) on disposition of property, plant and equipment	1,022	69	(139)
Changes in assets and liabilities:
Accounts receivable, net	966	(19,447)	2,665
Inventories	676	(14,016)	4,269
Prepaid expenses and other assets	(7,068)	(540)	(364)
Accounts payable	(3,354)	5,986	10,686
Accrued liabilities	(26,017)	13,434	10,194
Deferred revenue	(1,167)	1,744	(180)
Income taxes payable and prepaid taxes	4,962	(16,702)	8,850
Other liabilities	(6)	2,950	1,160
Net cash provided by operations	99,832	93,801	83,324
Cash flows from investing activities:
Purchase of available-for-sale investments	(93,330)	(168,802)	(245,187)
Proceeds from sales and maturities of available-for-sale investments	131,748	110,987	275,056
Proceeds from sale of property, plant and equipment	46	76	108
Purchases of property, plant and equipment	(21,564)	(25,537)	(8,682)
Purchase of intangible assets	(3,000)
Acquisitions, net of cash acquired			(178,061)
Net cash provided by (used in) investing activities	13,900	(83,276)	(156,766)
Cash flows from financing activities:
Excess tax benefit received on stock options	2,279	891	493
Exercise of stock options	42,661	29,823	11,288
Repurchase of outstanding common stock	(50,665)	(2,819)	(2,931)
Repayment of debt			(2,450)
Net cash (used in) provided by financing activities	(5,725)	27,895	6,400
Effect of exchange rate (decrease) increase on cash and cash equivalents	(4)	1	(26)
Net increase (decrease) in cash and cash equivalents	108,003	38,421	(67,068)
Cash and cash equivalents at beginning of period	119,019	80,598	147,666
Cash and cash equivalents at end of period	$ 227,022	$ 119,019	$ 80,598