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Employee Benefit Plans - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Feb. 29, 2020 USD ($) Retirement-Plan | Feb. 23, 2019 USD ($) | Feb. 29, 2020 USD ($) Retirement-Plan | Feb. 23, 2019 USD ($)
Postemployment Benefits [Abstract] |  |  |  |
Contributions charged to expense under the plan | $ 5.0 | $ 4.3 | $ 10.5 | $ 8.8
Number of frozen non-contributory defined benefit pension plans | Retirement-Plan | 2 |  | 2 |
Amounts charged to expense (benefit) related to the plans | $ (0.3) | $ 0.5 | $ 0.4 | $ 1.1

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- Definition Defined Benefit Plan, Number Of Frozen Plans + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits. + References No definition available. + Details
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- References No definition available. + Details
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