Share-Based Compensation By Share-Based Payment Award, Offering Period

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The maximum amount of contributions per share-based compensation plan during the offering period.

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Stock Issued During Period Employee Stock Purchase Plans Weighted Average Price Per Share

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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- 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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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- Definition

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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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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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

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock Based Compensation - Narrative (Details) - USD ($)			3 Months Ended		6 Months Ended
	Jan. 15, 2021	Nov. 09, 2020	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 11,000,000.0	$ 8,200,000	$ 22,300,000	$ 18,000,000.0
Unrecognized compensation expense related to non-vested equity			$ 107,100,000		$ 107,100,000
Weighted average period for recognition					3 years 2 months 12 days
Offering period					3 months
Purchase price percentage					85.00%
Maximum employee subscription rate			10.00%		10.00%
Maximum contribution limit					$ 25,000
Number of share purchased by employees (in shares)			9,528	11,493	18,797	22,652
Stock issued during period employee stock purchase plans weighted average price per share (in USD per share)			$ 263.18	$ 221.12	$ 274.72	$ 220.91
Capital shares reserved for future issuance (in shares)			159,007		159,007
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-option award grants (in shares)					41,511
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-option award grants (in shares)					36,424
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 500,000	$ 500,000	$ 1,000,000.0	$ 1,000,000.0
LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)			5,100,000		5,100,000
Stock options granted (in shares)					409,476
Exercise price (in USD per share)		$ 316.71			$ 316.69
LTIP \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		20.00%
Award vesting period		5 years
Expiration period		10 years
LTIP \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					5 years
Weighted average grant date fair value (in USD per share)					$ 306.36
LTIP \| Restricted stock units \| Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage					20.00%
LTIP \| Restricted stock units \| Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage					50.00%
LTIP \| Restricted stock units \| Share-based Payment Arrangement, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage					25.00%
Director Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)			237,749		237,749
Stock options granted (in shares)	12,137
Exercise price (in USD per share)	$ 318.20