Goodwill (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Sep. 30, 2025 |
|
| Goodwill | ||
| Goodwill (gross) | $ 5,575.6 | $ 5,574.5 |
| Accumulated impairment losses | (729.8) | (729.8) |
| Goodwill | 4,845.8 | 4,844.7 |
| Currency translation adjustment | 1.1 | |
| Post Consumer Brands | ||
| Goodwill | ||
| Goodwill (gross) | 2,408.8 | 2,408.7 |
| Accumulated impairment losses | (609.1) | (609.1) |
| Goodwill | 1,799.7 | 1,799.6 |
| Currency translation adjustment | 0.1 | |
| Foodservice | ||
| Goodwill | ||
| Goodwill (gross) | 1,389.2 | 1,389.2 |
| Accumulated impairment losses | 0.0 | 0.0 |
| Goodwill | 1,389.2 | 1,389.2 |
| Currency translation adjustment | 0.0 | |
| Refrigerated Retail | ||
| Goodwill | ||
| Goodwill (gross) | 835.3 | 835.3 |
| Accumulated impairment losses | (120.7) | (120.7) |
| Goodwill | 714.6 | 714.6 |
| Currency translation adjustment | 0.0 | |
| Weetabix | ||
| Goodwill | ||
| Goodwill (gross) | 942.3 | 941.3 |
| Accumulated impairment losses | 0.0 | 0.0 |
| Goodwill | 942.3 | $ 941.3 |
| Currency translation adjustment | $ 1.0 |
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- Definition Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) asset representing future economic benefit from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Includes amount, before amortization expense and impairment loss, of goodwill for private company. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated impairment loss for asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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