Marketable Securities (Tables)

6 Months Ended

Jul. 28, 2019

Investments, Debt and Equity Securities [Abstract]

Cash Equivalents and Marketable Securities

The following is a summary of cash equivalents and marketable securities as of July 28, 2019 and January 27, 2019:



	July 28, 2019
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value		Reported as
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value		Cash Equivalents		Marketable Securities
	(In millions)
Money market funds	$	2,868	$	—	$	—	$	2,868	$	2,868	$	—
Debt securities issued by the United States Treasury	2,161		—		—		2,161		1,833		328
Corporate debt securities	2,103		1		—		2,104		1,282		822
Debt securities of United States government agencies	1,120		—		—		1,120		995		125
Foreign government debt securities	45		—		—		45		—		45
Asset-backed securities	44		—		—		44		—		44
Certificates of deposit	24		—		—		24		24		—
Mortgage-backed securities issued by United States government-sponsored enterprises	6		—		—		6		—		6
Total	$	8,371	$	1	$	—	$	8,372	$	7,002	$	1,370



	January 27, 2019
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value		Reported as
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value		Cash Equivalents		Marketable Securities
	(In millions)
Corporate debt securities	$	2,626	$	—	$	(6	)	$	2,620	$	25	$	2,595
Debt securities of United States government agencies	2,284		—		(4		)	2,280		—		2,280
Debt securities issued by the United States Treasury	1,493		—		(1		)	1,492		176		1,316
Money market funds	483		—		—			483		483		—
Foreign government debt securities	209		—		—			209		—		209
Asset-backed securities	152		—		(1		)	151		—		151
Mortgage-backed securities issued by United States government-sponsored enterprises	88		1		—			89		—		89
Total	$	7,335	$	1	$	(12	)	$	7,324	$	684	$	6,640

The amortized cost and estimated fair value of cash equivalents and marketable securities as of July 28, 2019 and January 27, 2019 are shown below by contractual maturity.



	July 28, 2019				January 27, 2019
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(In millions)
Less than 1 year	$	8,255	$	8,255	$	5,042	$	5,034
Due in 1 - 5 years	112		113		2,271		2,268
Mortgage-backed securities issued by United States government-sponsored enterprises not due at a single maturity date	4		4		22		22
Total	$	8,371	$	8,372	$	7,335	$	7,324