WBX East Africa and Alpen (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Schedule of Equity Method Investments
Other assets	$ 366.9	$ 360.0
Alpen Food Company South Africa (Pty) Limited
Schedule of Equity Method Investments
Equity Method Investment, Ownership Percentage	50.00%
Alpen Food Company South Africa (Pty) Limited \| Equity Method Investments
Schedule of Equity Method Investments
Other assets	$ 3.7	$ 3.6
Post Holdings, Inc. \| Weetabix East Africa Limited
Schedule of Equity Method Investments
Noncontrolling Interest, Ownership Percentage by Parent	50.10%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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