Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2022	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2021
Cash distributions directly to related parties		$ 550.4
Other Restructuring Costs	$ 10.3	12.3
Payment of merger consideration		115.5	$ 0.0
7.00% Senior Notes Maturing in March 2030
Long-term debt, gross	$ 840.0	$ 840.0		$ 0.0
BellRing Common Stock \| Post Shareholders
Conversion of Stock, Shares Received		1.267788

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+ References

No definition available.

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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.

+ References

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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The cash outflow for financing costs associated with business combinations.

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