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Employee Benefit Plans - Narrative (Details) - USD ($) | 12 Months Ended
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Aug. 30, 2025 | Aug. 31, 2024 | Aug. 26, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Contributions charged to expense under the plan | $ 15,600,000 | $ 20,300,000 | $ 18,700,000
Other (income) expense | (400,000) | (600,000) | 0
SERP |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Amounts charged to expense related to the plan | 1,600,000 | 1,700,000 | 1,700,000
Accumulated benefit obligations | 21,700,000 | 23,400,000 |
UniFirst Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Amounts charged to expense related to the plan | 200,000 | 200,000 | 100,000
Accumulated benefit obligations | 3,000,000.0 | 3,600,000 |
Non-qualified Deferred Compensation Plan |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Amounts charged to expense related to the plan | 1,000,000 | 800,000 | $ 300,000
NQDC Plan assets | 4,700,000 | 3,300,000 |
NQDC Plan liabilities, current | $ 2,800,000 | $ 1,600,000 |

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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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