Share-Based Compensation Arrangement, Vesting, Number Of Installments

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- Definition

Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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- Definition

Amount of expense for employee benefit and equity-based compensation.

+ References

No definition available.

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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.

+ 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
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

+ References

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

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
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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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Shareholders’ Equity - Issuances/Repurchases (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020 USD ($) vesting_installment shares	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General and administrative expense \| $	$ 26,514	$ 28,706	$ 27,149
Compensation and benefits expense \| $	$ 131,095	$ 130,619	$ 122,916
Class A common shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	93,700	77,900	65,000
Managing Director \| Class A common shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	3,000	2,500	2,500
2016 Plan \| Class A common shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of installments \| vesting_installment	5
General and administrative expense \| $	$ 564	$ 784	$ 864
Adjustment related to tax withholding for share based compensation \| $	523	827	987
2016 Plan \| Officers and Employees \| Class A common shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and benefits expense \| $	$ 2,916	$ 2,579	$ 3,001
Restricted Stock Awards \| 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares nonvested (in shares)	143,990	126,160	110,240	104,020
Number of shares vested (in shares)	75,101	56,833	59,671
Estimated future compensation expense \| $	$ 6,350
Weighted average period compensation expense will be recorded (in years)	26 months
Shares available for future issuance (in shares)	204,359
Tranche One \| Restricted Stock Awards \| 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)	50,560
Tranche Two \| Restricted Stock Awards \| 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)	41,930
Tranche Three \| Restricted Stock Awards \| 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)	32,760
Tranche Four \| Restricted Stock Awards \| 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)	18,740