CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jul. 28, 2012	Jul. 30, 2011
Cash flows from operating activities:
Net income	$ 187,617	$ 339,253
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	42,484	46,474
Stock-based compensation	60,420	57,835
Amortization and write-off of acquired intangible assets	27,378	25,479
Other expense, net	5,175	7,145
Excess tax benefits from stock-based compensation	(44)	(14)
Changes in assets and liabilities:
Accounts receivable	16,491	53,649
Inventories	8,033	(76,004)
Prepaid expenses and other assets	15,635	17,438
Accounts payable	27,537	6,999
Accrued liabilities and other	13,939	(91)
Accrued employee compensation	(24,681)	(29,267)
Deferred income	7,881	(8,334)
Net cash provided by operating activities	387,865	440,562
Cash flows from investing activities:
Purchases of marketable securities	(646,907)	(1,139,884)
Purchases of strategic investments	(5,750)	(2,253)
Sales and maturities of investments	881,309	681,069
Cash paid for acquisition, net		(16,760)
Purchases of technology licenses	(6,452)	(6,615)
Purchases of property and equipment	(29,734)	(42,245)
Net cash provided by (used in) investing activities	192,466	(526,688)
Cash flows from financing activities:
Repurchase of common stock	(473,484)	(939,241)
Proceeds from employee stock plans	57,329	46,623
Minimum tax withholding paid on behalf of employees for net share settlement	(9,477)	(4,868)
Dividend payments to shareholders	(33,537)
Principal payments on capital lease obligations		(511)
Excess tax benefits from stock-based compensation	44	14
Net cash used in financing activities	(459,125)	(897,983)
Net increase (decrease) in cash and cash equivalents	121,206	(984,109)
Cash and cash equivalents at beginning of period	784,902	1,847,074
Cash and cash equivalents at end of period	$ 906,108	$ 862,965