Amount of accumulated amortization of debt issuance costs classified as noncurrent.

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Amount of amortization expense attributable to debt issuance costs.

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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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Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Long-term Debt and Line of Credit, Principal Repayments of Long-term Debt (FY) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2020
Long-term Debt, Principal Repayment [Abstract]
Long-term debt, gross	$ 76,926			$ 119,685
Less: Unamortized portion of capitalized debt issuance costs	(1,013)			$ (2,470)
OneWater LLC [Member]
Long-term Debt, Principal Repayment [Abstract]
2020	11,124
2021	7,075
2022	58,204
2023	356
2024	157
Thereafter	10
Long-term debt, gross	76,926	$ 42,973
Less: Unamortized portion of capitalized debt issuance costs	(1,013)	(1,129)
Long-term debt, net	75,913
Debt issuance costs, capitalized loan costs	200	700
Debt issuance costs, accumulated amortization	700	400
Debt issuance costs, amortization	$ 300	$ 200	$ 200