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Fair Value Measurements - Additional Information (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($)
$ in Thousands
Feb. 09, 2019
Aug. 25, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Short-term marketable debt securities $ 51,561 $ 59,444
Long-term marketable debt securities $ 70,183 $ 75,232