Number of regional groups.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Percentage of fair value of reporting unit in excess of carrying amount.

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No definition available.

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Goodwill and Other Intangible Assets, Net - Additional Information (Details)	12 Months Ended
	Aug. 31, 2021 USD ($) reporting_unit Regional	Aug. 31, 2020 USD ($) reporting_unit	Aug. 31, 2019 USD ($)	Jul. 01, 2021 USD ($)	Jul. 01, 2020
Goodwill [Line Items]
Goodwill	$ 170,304,000	$ 169,627,000	$ 169,237,000	$ 171,000,000
Number of reporting units \| reporting_unit	3
Number of regional groups \| Regional	2
Goodwill, impaired, accumulated impairment loss	$ 471,000,000	471,000,000
Amortization of intangible assets	1,000,000	1,000,000	1,000,000
Impairments of intangible assets recognized	$ 0	$ 0	$ 0
AMR
Goodwill [Line Items]
Number of reporting units \| reporting_unit	2	1
AMR \| Single Reporting Unit Carried Out
Goodwill [Line Items]
Goodwill		$ 1,000,000
Estimated fair value of reporting unit exceeded carrying amount					29.00%
AMR \| Two Reporting Unit Carried Out
Goodwill [Line Items]
Goodwill				$ 1,000,000