Amount of share-based compensation arrangements.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(ii)
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- Definition

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

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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Publisher FASB
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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

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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Stock-Based Compensation (Additional Information) (Detail)	3 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) item $ / shares shares	Sep. 30, 2019 USD ($) $ / shares	Jun. 30, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised \| $	$ 100,000	$ 500,000
Total pre-tax unrecognized compensation costs related to non-vested awards \| $	$ 27,300,000
Total pre-tax unrecognized compensation costs related to non-vested awards expected to be recognized, years	2 years 9 months 18 days
Total fair value of options and Restricted Stock Units vested \| $	$ 16,300,000	12,100,000
Share-based Payment Arrangement, Amount Capitalized \| $	$ 0	$ 0	$ 0
Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangements plans \| item	2
Weighted average estimated grant date fair values, for options granted at market price, per share \| $ / shares	$ 12.23	$ 16.98
Common Stock, Capital Shares Reserved for Future Issuance \| shares	3,803,197
Stock Incentive Plans \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options (in years)	10 years
Vesting Period (in years)	5 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares	$ 32.02	$ 43.39
Restricted Stock Units Outstanding, Shares Granted \| shares	332,890
Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options (in years)	3 years
Restricted Stock Units Outstanding, Shares Granted \| shares	1,590
Non-Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options (in years)	3 years
Restricted Stock Units Outstanding, Shares Granted \| shares	331,300
Non-Performance Based Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options (in years)	1 year
Non-Performance Based Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options (in years)	4 years