Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Property and Equipment (FY) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, net	$ 16,785	$ 16,785		$ 15,954
Depreciation and amortization expense	$ 824	$ 2,375	$ 1,883
OneWater LLC [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				21,275	$ 21,669
Less accumulated depreciation				(5,321)	(3,082)
Property, plant and equipment, net				15,954	18,587
Depreciation and amortization expense				2,682	1,685	$ 1,055
OneWater LLC [Member] \| Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				1,066	4,640
OneWater LLC [Member] \| Buildings and Improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				336	2,402
OneWater LLC [Member] \| Leasehold Improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				5,197	3,558
OneWater LLC [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				4,743	3,837
OneWater LLC [Member] \| Office Equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				3,795	2,758
OneWater LLC [Member] \| Company Vehicles [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				4,537	3,218
OneWater LLC [Member] \| Construction in Progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property, plant and equipment, gross				$ 1,601	$ 1,256