Fair Value Measurements - Company's marketable debt securities measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Feb. 15, 2020	Aug. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 124,447	$ 138,926
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets	47,951	67,958
Other long-term assets	76,496	70,968
Total	124,447	138,926
Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets	47,079	65,344
Other long-term assets	67,355	65,573
Total	114,434	130,917
Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets	872	2,614
Other long-term assets	9,141	5,395
Total	10,013	8,009
Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other current assets
Other long-term assets
Total