CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Oct. 27, 2013	Oct. 28, 2012
Cash flows from operating activities:
Net income	$ 293,073	$ 388,563
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	184,310	167,834
Stock based compensation expense	100,091	100,893
Deferred income taxes	7,914	42,684
Excess Tax benefit from stock based compensation	(23,743)	(25,646)
Other	11,311	39,978
Changes in operating assets and liabilities, net of effect of acquisition:
Accounts receivable	7,806	(109,008)
Inventories	32,178	(88,378)
Prepaid expenses and other current assets	(4,687)	(16,786)
Other assets	7,585	4,784
Accounts payable	(38,376)	49,099
Accrued liabilities and other long-term liabilities	(143,028)	(180,854)
Net cash provided by operating activities	434,434	373,163
Cash flows from investing activities:
Purchases of marketable securities	(1,420,471)	(1,729,307)
Proceeds from sale of marketable securities	1,475,403	635,733
Proceeds from maturities of marketable securities	447,134	626,434
Purchases of property and equipment and intangible assets	(188,812)	(135,551)
Acquisition of business	(17,145)	0
Other	(2,450)	135
Net cash provided by (used in) investing activities	293,659	(602,556)
Cash flows from financing activities:
Proceeds from issuance of common stock under employee stock plans	64,749	62,781
Excess Tax benefit from Stock based compensation	23,743	25,646
Payments for Repurchase of Common Stock	(850,000)	0
Dividend paid	(133,007)	0
Other Financing Activities	(4,280)	(1,522)
Net cash provided by (used in) financing activities	(898,795)	86,905
Change in cash and cash equivalents	(170,702)	(142,488)
Cash and cash equivalents at beginning of period	732,786	667,876
Cash and cash equivalents at end of period	562,084	525,388
Supplemental disclosures of cash flow information:
Cash paid or (received) for income taxes, net	8,454
Proceeds from Income Tax Refunds		(40,442)
Cash paid for interest on capital lease obligations	1,915	2,189
Other non-cash activities:
Assets acquired by assuming related liabilities	28,963	43,792
Change in unrealized gains (losses) from marketable securities	$ (4,119)	$ 246