Marketable Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 29, 2018	Dec. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Term of maturities of investments considered short-term	2 years
Maturing within one year	$ 7,435	$ 4,982
Maturing between one and two years	2,165	0
Total marketable securities	$ 9,600	$ 4,982

Term Of Maturities Of Investments Considered Short-Term

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Amount of investment in marketable security.

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Amount of investment in marketable security, classified as current.

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Amount of investment in marketable security, classified as noncurrent.

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