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Summary of Significant Accounting Policies - Narrative (Details) | 12 Months Ended
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Aug. 28, 2021 USD ($) segment shares | Aug. 29, 2020 USD ($) shares | Aug. 31, 2019 USD ($) shares | Aug. 31, 2019
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Number of reporting segments | segment | 5 |  |  |
Short-term investments | $ 0 | $ 0 |  |
Percentage of revenues derived from route servicing fees | 91.30% |  |  |
Current assets related to deferred commissions | $ 14,200,000 | 13,300,000 |  |
Noncurrent assets related to deferred commissions | 60,600,000 | 55,600,000 |  |
Amortization expense related to deferred commissions | $ 14,400,000 | 13,700,000 |  |
Estimated service lives of rental merchandise, minimum | 6 months |  |  |
Estimated service lives of rental merchandise, maximum | 36 months |  |  |
Impairment of goodwill and definite-lived intangible assets | $ 0 | 0 | $ 0 |
Weighted average useful life | 11 years 10 months 24 days |  |  |
Discount rate, lower range | 1.31% |  |  |
Discount range, upper range | 1.91% |  |  |
Inflation rate | 3.00% |  |  |
Advertising costs | $ 3,500,000 | $ 3,800,000 | $ 3,600,000 |
Anti-dilutive securities excluded from calculation of diluted earnings per share (in shares) | shares | 6,005 | 8,094 | 8,325 |
Accounting Standards Update 2016-13 |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Change in accounting principle, accounting standards update, adoption date | Aug. 30, 2020 |  |  |
Change in accounting principle, accounting standards update, adopted | true |  |  |
Change in accounting principle, accounting standards update, immaterial effect | true |  |  |
Accounting Standards Update 2017-07 |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Change in accounting principle, accounting standards update, adoption date | Aug. 29, 2021 |  |  |
Change in accounting principle, accounting standards update, adopted | true |  |  |
Change in accounting principle, accounting standards update, immaterial effect | true |  |  |
Accounting Standards Update 2018-15 |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Change in accounting principle, accounting standards update, adoption date | Aug. 30, 2020 |  |  |
Change in accounting principle, accounting standards update, adopted | true |  |  |
Change in accounting principle, accounting standards update, immaterial effect | true |  |  |
Conversion of Class B Common Stock in to Common Stock |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Conversion ratio | 1 |  |  |
Stock Appreciation Rights (SARs) |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Expiration period | 10 years |  |  |
Stock Appreciation Rights (SARs) | Certain Share-based Awards Granted During Fiscal 2020, 2019 and 2018 to Non-employee Directors | Non-Employee Directors |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Expiration period | 8 years |  |  |
Minimum |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Discount period, lower range | 10 years |  |  |
Remaining lives | 1 year |  |  |
Credit adjusted risk-free rate | 7.00% |  |  |
Maximum |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Discount period, lower range | 30 years |  |  |
Remaining lives | 25 years |  |  |
Credit adjusted risk-free rate | 7.50% |  |  |
Customer contracts |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Weighted average useful life | 13 years 6 months |  |  |
Other intangible assets |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Weighted average useful life | 9 years 7 months 6 days |  |  |
Core Laundry Operations |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of revenues recognized over time | 95.80% | 94.70% |  | 95.80%
Percentage of revenues recognized at a point in time | 4.20% | 5.30% |  | 4.20%
Specialty Garments |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of revenues recognized over time | 81.80% | 79.20% |  | 82.70%
Percentage of revenues recognized at a point in time | 18.20% | 20.80% |  | 17.30%
First Aid |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of revenues recognized at a point in time | 100.00% |  |  |

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