Long-term Debt and Line of Credit (Details) - OneWater LLC [Member] - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Sep. 30, 2019
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 74,840	$ 76,926
Less current portion	(6,823)	(11,124)
Less unamortized portion of debt issuance costs	(1,004)	(1,013)
Long-term debt, net	67,013	64,789
Multi-Draw Term Note Payable to Goldman Sachs Specialty Lending Group, L.P. and Owm Bip Investor, LLC, Secured and Bearing Interest at 10.0% Per Annum, Refinanced on February 11, 2020 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 57,203	58,000
Interest rate	10.00%
Revolving note payable to Goldman Sachs Specialty Lending Group, L.P. and OWM BIP Investor, LLC, secured and bearing interest at 10.0% per annum. Refinanced on February 11, 2020 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 0	0
Interest rate	10.00%
Maximum borrowing capacity	$ 5,000
Note Payable To Rambo Marine, Inc., Unsecured And Bearing Interest at 7.5% Per Annum. the Note Requires Annual Interest Payments, with a Balloon Payment of Principal Due on July 1, 2020 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 3,133	3,133
Interest rate	7.50%
Maturity date	Jul. 01, 2020
Note Payable to Commercial Vehicle Lenders Secured by the Value of the Vehicles Bearing Interest at Rates Ranging From 0.0% to 8.9% Per Annum. the Note Requires Monthly Installment Payments of Principal and Interest Ranging from $100 to $5,600 Through July 2025 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 2,482	2,371
Maturity date	Jul. 31, 2025
Frequency of periodic payment	Monthly
Note Payable to Commercial Vehicle Lenders Secured by the Value of the Vehicles Bearing Interest at Rates Ranging From 0.0% to 8.9% Per Annum. the Note Requires Monthly Installment Payments of Principal and Interest Ranging from $100 to $5,600 Through July 2025 [Member] \| Minimum [Member]
Long-term Debt and Line of Credit [Abstract]
Interest rate	0.00%
Monthly installment payment amount	$ 100
Note Payable to Commercial Vehicle Lenders Secured by the Value of the Vehicles Bearing Interest at Rates Ranging From 0.0% to 8.9% Per Annum. the Note Requires Monthly Installment Payments of Principal and Interest Ranging from $100 to $5,600 Through July 2025 [Member] \| Maximum [Member]
Long-term Debt and Line of Credit [Abstract]
Interest rate	8.90%
Monthly installment payment amount	$ 5,600
Note Payable to Central Marine Services, Inc., Unsecured and Bearing Interest at 5.5% Per Annum, the Note Requires Monthly Interest Payments, with a Balloon Payment of Principal Due On February 1, 2022 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 2,164	2,164
Interest rate	5.50%
Maturity date	Feb. 01, 2022
Note Payable to Marina Mikes, LLC, Unsecured and Bearing Interest at 5.0% Per Annum, the Note Requires Annual Interest Payments, with a Balloon Payment of Principal Due on June 1, 2020 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 2,125	2,125
Interest rate	5.00%
Maturity date	Jun. 01, 2020
Note Payable to Ocean Blue Yacht Sales, Unsecured and Bearing Interest at 5.0% Per Annum, the Note Requires Quarterly Interest Payments, with a Balloon Payment of Principal Due on February 1, 2022 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 1,920	1,920
Interest rate	5.00%
Maturity date	Feb. 01, 2022
Note Payable to Lab Marine, Inc., Unsecured and Bearing Interest at 6.0% Per Annum, the Note Requires Annual Interest Payments, with a Balloon Payment of Principal Due on March 1, 2021 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 1,500	1,500
Interest rate	6.00%
Maturity date	Mar. 01, 2021
Note Payable to Sunrise Marine, Inc. and Sunrise Marine of Alabama, Inc., Unsecured and Bearing Interest at 6.0% Per Annum [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 0	1,400
Interest rate	6.00%
Note Payable to Slalom Shop, LLC, Unsecured and Bearing Interest at 5.0% Per Annum the Note Requires Quarterly Interest Payments, with a Balloon Payment of Principal Due on December 1, 2021 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 1,271	1,271
Interest rate	5.00%
Maturity date	Dec. 01, 2021
Note Payable to Bosun's Marine, Inc., Unsecured and Bearing Interest at 4.5% Per Annum, the Note Requires Annual Interest Payments with a Balloon Payment Due on June 1, 2021 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 1,227	1,227
Interest rate	4.50%
Maturity date	Jun. 01, 2021
Note Payable to Rebo, Inc., Unsecured and Bearing Interest at 5.5% Per Annum, the note Requires Annual Interest Payments with a Balloon Payment Due on April 1, 2021 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 1,000	1,000
Interest rate	5.50%
Maturity date	Apr. 01, 2021
Note Payable to Texas Marine, Inc., Unsecured and Bearing Interest at 4.5% Per Annum, the Note Requires Annual Interest Payments, with a Balloon Payment of Principal Due on August 1, 2020 [Member]
Long-term Debt and Line of Credit [Abstract]
Long-term debt, gross	$ 815	$ 815
Interest rate	4.50%
Maturity date	Aug. 01, 2020

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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