Potential number of performance based shares to be granted

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- Definition

Restricted stock grant fair value.

+ References

No definition available.

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- Definition

Stockholders Equity Note [Line Items]

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Section 50
-Paragraph 2
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the YYYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased and retired during the period.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity - Additional Information (Detail) - USD ($)	12 Months Ended
Equity - Additional Information (Detail) - USD ($)	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019	Jan. 06, 2021
Stockholders Equity Note [Line Items]
Shares repurchased	$ 20,000,000.0
Shares available for grant	1,618,230	465,636	849,522
Performance based share based compensation and dividend equivalent rights	538,260	469,825	313,540
Share based compensation, non vested shares	622,528
Additional shares available for grant	622,528
Unamortized compensation cost of restricted stock unit grants	$ 13,300,000
Share Repurchase Program - 2014
Stockholders Equity Note [Line Items]
Remaining authorized repurchase amount	$ 100,000,000.0
Repurchase program expiration date	Jan. 31, 2023
Repurchase of common stock, shares	0	0
Selling, Administrative and Cost of Revenue
Stockholders Equity Note [Line Items]
Restricted stock compensation expense	$ 14,700,000	$ 8,700,000	$ 12,400,000
Restricted Stock \| Minimum
Stockholders Equity Note [Line Items]
Vesting period of compensation expense	1 year
Restricted Stock \| Maximum
Stockholders Equity Note [Line Items]
Vesting period of compensation expense	3 years
Unvested Restricted Stock Grants
Stockholders Equity Note [Line Items]
Share based compensation, non vested shares	1,023,504	883,933
Fair value of awards granted	$ 18,000,000.0	$ 14,500,000	$ 17,400,000
2021 Stock Incentive Plan and 2017 Amended and Restated Stock Incentive Plan
Stockholders Equity Note [Line Items]
Number of shares reserved for future issuance				1,500,000
2021 Stock Incentive Plan and 2017 Amended and Restated Stock Incentive Plan \| Maximum
Stockholders Equity Note [Line Items]
Shares available for grant				465,636
Number of common shares outstanding				883,933