Share based compensation arrangement by share based payment award redeemed units in period.

No definition available.

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- Definition

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

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- Definition

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

Amount of noncash expense for share-based payment arrangement.

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-Publisher FASB
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-SubTopic 10
-Section 45
-Paragraph 28
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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 equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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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 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.

+ References

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

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

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				12 Months Ended
	Nov. 19, 2020	Nov. 14, 2020	Nov. 14, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Mar. 10, 2020	Oct. 22, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock options forfeited				355,000
Stock option vested and exercisable upon issuance				3,432,000
Stock options granted				687,000
Granted, weighted average exercise price				$ 13.78
Number of shares exercised				26,000
Equity-based compensation				$ 19.7	$ 23.6	$ 15.7
Unrecognized compensation cost				$ 25.6	$ 36.2	$ 40.2
Unrecognized compensation cost, weighted average recognition period				1 year 2 months 12 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Units granted				876,000
Units redemption				221,000
Units forfeited or canceled				105,000
Units outstanding				1,299,000	749,000
Share issued to holders of units				876,000
Stock options weighted average grant date fair value				$ 14.28
Non-cash equity-based compensation expense over the requisite service period				$ 10.5
Granted, weighted average exercise price				$ 14.28
Number of shares exercised				221,000
Common stock shares issued				876,000
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted
Units redemption				253,000
Units forfeited or canceled				68,000
Units outstanding				802,000	1,123,000
Granted, weighted average exercise price
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
Share issued to holders of units	687,000
Stock options weighted average grant date fair value	$ 6.71
Weighted average exercise price	$ 13.78
Non-cash equity-based compensation expense over the requisite service period	$ 4.1
Number of shares forfeited				355,000
Number of shares exercised				26,000
Common stock shares issued	687,000
Amended and Restated 2018 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock that may be issued							18,650,000
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share issued to holders of units		120,000	172,000
Common stock shares available for sale								1,100,000
Common stock shares issued		120,000	172,000