Summarizes Cost And Estimated Fair Value Of Short Term Fixed Income Securities (Detail) - USD ($) $ in Thousands	Jan. 01, 2016	Jan. 02, 2015
Fair Value Measurements [Line Items]
Due within one year, Amortized Cost	$ 19,948
Due between one and two years, Amortized Cost	26,000
Total Amortized Cost	45,948
Due within one year, Estimated Fair Value	19,950
Due between one and two years, Estimated Fair Value	25,892
Total Estimated Fair Value	$ 45,842	$ 24,913