Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 169,293	$ 171,449
Gross Unrealized Gains	1	1,456
Gross Unrealized Losses	10,764	1,312
Fair Value	158,530	171,593
Money market investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	21,910	8,750
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	21,910	8,750
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	18,905	22,441
Gross Unrealized Gains	0	0
Gross Unrealized Losses	2,889	346
Fair Value	16,016	22,095
Corporate bonds and direct obligations of government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	126,134	137,916
Gross Unrealized Gains	1	1,406
Gross Unrealized Losses	7,775	966
Fair Value	118,360	138,356
U.S. Treasury obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,344	2,342
Gross Unrealized Gains	0	50
Gross Unrealized Losses	100	0
Fair Value	$ 2,244	$ 2,392

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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