Financial Instruments - (Tables)

6 Months Ended

Aug. 01, 2021

Investments, Debt and Equity Securities [Abstract]

Cash Equivalents, Marketable Securities and Restricted Cash

The following tables summarize our cash equivalents, marketable securities and restricted cash by significant investment categories and their classification within the valuation hierarchy at the end of fiscal 2021 and the second quarter of fiscal 2022 (in thousands):

 

	At the End of Fiscal 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash Equivalents		Marketable Securities		Restricted Cash
Level 1
Money market accounts	$	—	$	—	$	—	$	49,984	$	39,440	$	—	$	10,544
Level 2
U.S. government treasury notes	339,253		3,241		(1)		342,493		15,340		327,153		—
U.S. government agencies	56,729		516		—		57,245		—		57,245		—
Corporate debt securities	425,115		4,176		(33)		429,258		—		429,258		—
Foreign government bonds	21,486		307		—		21,793		—		21,793		—
Asset-backed securities	79,924		1,015		—		80,939		—		80,939		—
Total	$	922,507	$	9,255	$	(34)	$	981,712	$	54,780	$	916,388	$	10,544

	At the End of the Second Quarter of Fiscal 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Cash Equivalents		Marketable Securities		Restricted Cash
Level 1
Money market accounts	$	—	$	—	$	—	$	29,449	$	18,905	$	—	$	10,544
Level 2
U.S. government treasury notes	341,033		1,842		(8)		342,867		10,000		332,867		—
U.S. government agencies	54,741		322		—		55,063		—		55,063		—
Corporate debt securities	465,168		2,535		(48)		467,655		—		467,655		—
Foreign government bonds	17,281		177		—		17,458		—		17,458		—
Asset-backed securities	68,331		477		(4)		68,804		—		68,804		—
Municipal bonds	2,440		—		(2)		2,438		—		2,438		—
Total	$	948,994	$	5,353	$	(62)	$	983,734	$	28,905	$	944,285	$	10,544

Amortized Cost and Estimated Fair Value

The amortized cost and estimated fair value of our marketable securities are shown below by contractual maturity (in thousands):

	At the End of the Second Quarter of Fiscal 2022
	Amortized Cost		Fair Value
Due within one year	$	355,927	$	358,013
Due in one to five years	579,137		582,333
Due in five to ten years	3,930		3,939
Total	$	938,994	$	944,285

Gross Unrealized Losses and Fair Values

The following table presents gross unrealized losses and fair values for those investments that were in a continuous unrealized loss position at the end of fiscal 2021 and the second quarter of fiscal 2022, aggregated by investment category (in thousands):

	At the End of Fiscal 2021
	Less than 12 months				Greater than 12 months				Total
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U.S. government treasury notes	$	8,301	$	(1)	$	—	$	—	$	8,301	$	(1)
Corporate debt securities	32,996		(33)		—		—		32,996		(33)
Total	$	41,297	$	(34)	$	—	$	—	$	41,297	$	(34)

	At the End of the Second Quarter of Fiscal 2022
	Less than 12 months				Greater than 12 months				Total
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U.S. government treasury notes	$	33,652	$	(8)	$	—	$	—	$	33,652	$	(8)
Corporate debt securities	44,011		(48)		—		—		44,011		(48)
Asset-backed securities	3,917		(4)		—		—		3,917		(4)
Municipal bonds	2,438		(2)		—		—		2,438		(2)
Total	$	84,018	$	(62)	$	—	$	—	$	84,018	$	(62)