Marketable Securities (Tables)

12 Months Ended

Jan. 26, 2014

Notes to financial statements [Abstract]

Cash Equivalents and Marketable Securities

	January 26, 2014
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
	(In thousands)
Debt securities of United States government agencies	$	1,012,740	$	848	$	(261	)	$	1,013,327
Corporate debt securities	1,827,788		1,857		(1,065		)	1,828,580
Mortgage backed securities issued by United States government-sponsored enterprises	185,594		3,837		(725		)	188,706
Money market funds	307,865		—		—			307,865
Debt securities issued by United States Treasury	495,889		621		(57		)	496,453
Asset-backed securities	258,017		15		(315		)	257,717
Total	$	4,087,893	$	7,178	$	(2,423	)	$	4,092,648
Classified as:
Cash equivalents								$	572,425
Marketable securities								3,520,223
Total								$	4,092,648

	January 27, 2013
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
	(In thousands)
Debt securities of United States government agencies	$	867,087	$	1,199	$	(139	)	$	868,147
Corporate debt securities	1,255,297		3,175		(542		)	1,257,930
Mortgage backed securities issued by United States government-sponsored enterprises	183,034		6,194		(57		)	189,171
Money market funds	195,790		—		—			195,790
Debt securities issued by United States Treasury	785,228		1,102		(105		)	786,225
Total	$	3,286,436	$	11,670	$	(843	)	$	3,297,263
Classified as:
Cash equivalents								$	302,166
Marketable securities								2,995,097
Total								$	3,297,263

The following table provides the breakdown of the investments with unrealized losses at January 26, 2014:

	Less than 12 months					12 months or greater					Total
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
	(In thousands)
Corporate debt securities	$	789,095	$	(87	)	$	1,039,485	$	(978	)	$	1,828,580	$	(1,065	)
Mortgage backed securities issued by United States government-sponsored enterprises	999		—			187,707		(725		)	188,706		(725		)
Debt securities of United States Treasury	88,984		(9		)	407,469		(48		)	496,453		(57		)
Debt securities issued by United States government agencies	576,920		(100		)	436,407		(161		)	1,013,327		(261		)
Asset-backed securities	119,889		(119		)	137,828		(196		)	257,717		(315		)
Total	$	1,575,887	$	(315	)	$	2,208,896	$	(2,108	)	$	3,784,783	$	(2,423	)

Schedule of Cash Equivalents and Marketable Securities Available for Sale

	January 26, 2014				January 27, 2013
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(In thousands)
Less than one year	$	1,883,132	$	1,883,753	$	1,397,350	$	1,399,304
Due in 1 - 5 years	2,114,289		2,117,387		1,777,785		1,783,103
Mortgage-backed securities issued by government-sponsored enterprises not due at a single maturity date	90,472		91,508		111,301		114,856
Total	$	4,087,893	$	4,092,648	$	3,286,436	$	3,297,263