Summarizes Cost And Estimated Fair Value Of Short Term Fixed Income Securities (Detail) - USD ($) $ in Thousands	Sep. 27, 2019	Dec. 28, 2018
Fair Value Disclosures [Abstract]
Due within one year, Amortized Cost	$ 51,939
Due between one and two years, Amortized Cost	24,828
Total Amortized Cost	76,767
Due within one year, Estimated Fair Value	52,047
Due between one and two years, Estimated Fair Value	25,078
Total Estimated Fair Value	$ 77,125	$ 81,495

Available for sale securities debt maturities in next one to two years amortized cost.

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- Definition

Available for sale securities debt maturities in next one to two years fair value.

+ References

No definition available.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amortized cost of investment in debt security measured at fair value with change recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, 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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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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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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