Marketable Securities (Tables)

12 Months Ended

Dec. 26, 2021

Investments, Debt and Equity Securities [Abstract]

Schedule of Amortized Cost, Gross Unrealized Gains and Losses, and Fair Market Value of AFS Securities

The following tables present the amortized cost, gross unrealized gains and losses, and fair market value of our AFS securities as of December 26, 2021, and December 27, 2020:

	December 26, 2021
(In thousands)	Amortized Cost		Gross unrealized gains		Gross unrealized losses		Fair Value
Short-term AFS securities
U.S. Treasury securities	$	148,899	$	692	$	(43)	$	149,548
Corporate debt securities	107,158		245		(69)		107,334
Certificates of deposit	55,551		—		—		55,551
Commercial paper	21,145		—		—		21,145
Municipal securities	3,999		—		(2)		3,997
U.S. governmental agency securities	3,500		—		—		3,500
Total short-term AFS securities	$	340,252	$	937	$	(114)	$	341,075
Long-term AFS securities
Corporate debt securities	$	242,764	$	149	$	(1,858)	$	241,055
U.S. Treasury securities	119,695		—		(549)		119,146
U.S. governmental agency securities	39,498		—		(252)		39,246
Municipal securities	13,994		—		(61)		13,933
Total long-term AFS securities	$	415,951	$	149	$	(2,720)	$	413,380

	December 27, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Short-term AFS securities
U.S. Treasury securities	$	79,467	$	39	$	(3)	$	79,503
Corporate debt securities	129,805		504		(8)		130,301
Certificates of deposit	36,525		—		—		36,525
Commercial paper	37,580		—		—		37,580
U.S. governmental agency securities	25,113		61		(3)		25,171
Total short-term AFS securities	$	308,490	$	604	$	(14)	$	309,080
Long-term AFS securities
Corporate debt securities	$	134,296	$	1,643	$	(5)	$	135,934
U.S. Treasury securities	95,511		2,054		—		97,565
U.S. governmental agency securities	48,342		19		(13)		48,348
Municipal securities	4,994		—		(10)		4,984
Total long-term AFS securities	$	283,143	$	3,716	$	(28)	$	286,831

Schedule of AFS Securities in Unrealized Loss Position

The following tables present the AFS securities as of December 26, 2021, and December 27, 2020, that were in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by investment category and the length of time that individual securities have been in a continuous loss position:

	December 26, 2021
	Less than 12 Months				12 Months or Greater				Total
(In thousands)	Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses
Short-term AFS securities
U.S. Treasury securities	$	61,018	$	(43)	$	—	$	—	$	61,018	$	(43)
Corporate debt securities	53,148		(69)		—		—		53,148		(69)
Municipal securities	1,998		(2)		—		—		1,998		(2)
Total short-term AFS securities	$	116,164	$	(114)	$	—	$	—	$	116,164	$	(114)
Long-term AFS securities
Corporate debt securities	$	224,022	$	(1,858)	$	—	$	—	$	224,022	$	(1,858)
U.S. Treasury securities	119,146		(549)		—		—		119,146		(549)
U.S. governmental agency securities	39,246		(252)		—		—		39,246		(252)
Municipal securities	13,933		(61)		—		—		13,933		(61)
Total long-term AFS securities	$	396,347	$	(2,720)	$	—	$	—	$	396,347	$	(2,720)

	December 27, 2020
	Less than 12 Months				12 Months or Greater				Total
(In thousands)	Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses
Short-term AFS securities
U.S. Treasury securities	$	20,133	$	(3)	$	—	$	—	$	20,133	$	(3)
Corporate debt securities	33,735		(8)		—		—		33,735		(8)
U.S. governmental agency securities	4,999		(2)		8,749		(1)		13,748		(3)
Total short-term AFS securities	$	58,867	$	(13)	$	8,749	$	(1)	$	67,616	$	(14)
Long-term AFS securities
Corporate debt securities	$	6,717	$	(5)	$	—	$	—	$	6,717	$	(5)
U.S. governmental agency securities	26,236		(13)		—		—		26,236		(13)
Municipal securities	4,984		(10)		—		—		4,984		(10)
Total long-term AFS securities	$	37,937	$	(28)	$	—	$	—	$	37,937	$	(28)