Share-Based Payments - Additional Informations (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Feb. 13, 2021	Feb. 15, 2020	Feb. 13, 2021	Feb. 15, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted			196,161	188,324
Weighted average grant date fair value of options granted			$ 299.86	$ 252.39
Stock options exercised - shares			138,705	105,860
Stock options exercised - weighted average exercise price			$ 484.13	$ 476.60
Share-based compensation expense	$ 13.7	$ 12.1	$ 24.2	$ 22.1
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period			4 years
Non vested restricted stock unit award	$ 13.3		$ 13.3
Estimated weighted average period			2 years 10 months 24 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive shares excluded from the computation of earnings per share	196,280	188,486	248,578	147,998

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Number of share options (or share units) exercised during the current period.

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