Financial Instruments - Contractual Maturities of Available-For-Sale Securities (Detail) $ in Thousands	Dec. 30, 2018 USD ($)
Investments Debt And Equity Securities [Abstract]
Amortized Cost, Due in one year or less	$ 19,946
Amortized Cost, Due after one through five years	5,523
Amortized Cost	25,469
Fair Value, Due in one year or less	19,975
Fair Value, Due after one through five years	5,537
Fair Value	$ 25,512

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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