XML 63 R47.htm IDEA: XBRL DOCUMENT v3.8.0.1
Share-Based Payments - Weighted Average for Key Assumptions Used in Determining Fair Value of Options Granted and Related Share-Based Compensation Expense (Detail)
12 Months Ended
Aug. 26, 2017
Aug. 27, 2016
Aug. 29, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Expected price volatility 18.00% 18.00% 20.00%
Risk-free interest rates 1.20% 1.50% 1.40%
Weighted average expected lives (in years) 5 years 1 month 6 days 5 years 1 month 6 days 5 years 1 month 6 days
Forfeiture rate 10.00% 10.00% 9.00%
Dividend yield 0.00% 0.00% 0.00%