Expense related to the performance awards.

No definition available.

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- Definition

The number of awards granted during the period.

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No definition available.

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- Definition

The number of years for income projections in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- References

No definition available.

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- Definition

Fair value of share-based awards forfeited during the period.

+ References

No definition available.

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- Definition

Fair value of share-based awards granted during the period.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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

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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Equity-Based Compensation (FY) (Details) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) Award $ / shares shares	Sep. 30, 2018 USD ($) Award $ / shares shares	Sep. 30, 2017 USD ($) Award $ / shares shares
Weighted Average Grant Date Fair Value [Roll Forward]
Expense related to performance award \| $	$ 0.2	$ 0.3
Performance Share Unit [Member]
Award vesting period [Abstract]
Award vesting period		4 years
Non-Vested Profits in Interests [Roll Forward]
Granted (in shares)		67,000
OneWater LLC [Member] \| Performance Share Unit [Member]
Non-Vested Profits in Interests [Roll Forward]
Beginning balance (in shares)		2,573	3,329	3,500
Granted (in shares)				2,529	2,500
Forfeited (in shares)				(2,187)
Vested (in shares)			(756)	(513)
Ending balance (in shares)			2,573	3,329	3,500
Vested Profits in Interests [Roll Forward]
Beginning balance (in shares)		1,269	513	0
Vested (in shares)			756	513
Ending balance (in shares)			1,269	513	0
Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance (in dollars per share) \| $ / shares		$ 348	$ 352	$ 356
Granted (in dollars per share) \| $ / shares				193
Forfeited (in dollars per share) \| $ / shares				189
Vested (in dollars per share) \| $ / shares			366	437
Ending balance (in dollars per share) \| $ / shares			$ 348	$ 352	$ 356
Number of awards granted \| Award			0	5	3
Grant date fair value of units granted \| $				$ 0.5	$ 0.5
Number of years for income projections			5 years
Grant date fair value of units forfeited \| $				0.4
Grant date fair value of units vested \| $			$ 0.3	0.2
Expense related to performance award \| $			0.2	$ 0.2
Unrecognized compensation expense \| $			$ 0.5
Weighted-average period of recognition			1 year 4 months 24 days
Compensation expense \| $					$ 0.4
OneWater LLC [Member] \| Performance Share Unit [Member] \| Minimum [Member]
Award vesting period [Abstract]
Award vesting period			3 years
OneWater LLC [Member] \| Performance Share Unit [Member] \| Maximum [Member]
Award vesting period [Abstract]
Award vesting period			5 years