CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Oct. 26, 2014	Oct. 27, 2013
Cash flows from operating activities:
Net income	$ 437,459	$ 293,073
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	166,170	184,310
Stock-based compensation expense	115,371	100,091
Amortization of debt discount	20,884	0
Net gain on sale and disposal of long-lived assets and investments	(17,654)	(258)
Deferred income taxes	62,081	7,914
Tax benefits from stock based compensation	(11,744)	(23,743)
Others	19,343	11,569
Changes in operating assets and liabilities:
Accounts receivable	(138,729)	7,806
Inventories	(19,875)	32,178
Prepaid expenses and other assets	5,024	2,898
Accounts payable	9,827	(38,376)
Accrued liabilities and other current liabilities	(23,356)	34,296
Other long-term liabilities	(161,874)	(177,324)
Net cash provided by operating activities	462,927	434,434
Cash flows from investing activities:
Purchases of marketable securities	(2,126,079)	(1,420,471)
Proceeds from sale of marketable securities	1,100,014	1,475,403
Proceeds from maturities of marketable securities	688,168	447,134
Proceeds from sale of long-lived assets and investments	20,862	0
Purchases of property and equipment and intangible assets	(91,336)	(188,812)
Acquisition of business	0	(17,145)
Other	(500)	(2,450)
Net cash provided by (used in) investing activities	(408,871)	293,659
Cash flows from financing activities:
Proceeds from issuance of common stock under employee stock plans	129,691	64,749
Payments under capital lease obligations	(2,160)	(1,780)
Tax benefits from stock-based compensation	11,744	23,743
Payments for repurchase of common stock	(810,000)	(850,000)
Dividends paid	(140,235)	(133,007)
Other	0	(2,500)
Net cash used in financing activities	(810,960)	(898,795)
Change in cash and cash equivalents	(756,904)	(170,702)
Cash and cash equivalents at beginning of period	1,151,587	732,786
Cash and cash equivalents at end of period	394,683	562,084
Other non-cash activity:
Assets acquired by assuming related liabilities	$ 14,498	$ 28,963