Contingencies and commitments (Details) $ in Millions	3 Months Ended
Oct. 31, 2023 USD ($) item	Jul. 31, 2023 USD ($)
Lawsuit Related To Sale Of Jamex Transfer Services
Contingencies and commitments
Number of former officers \| item	2
Ferrellgas Partners Finance Corp
Contingencies and commitments
Debt securities outstanding	$ 0.0
Ferrellgas Finance Corp \| Senior Notes 5.375 Percent Due 2026
Contingencies and commitments
Liability as co-issuer	650.0	$ 650.0
Ferrellgas Finance Corp \| Senior Notes 5.875 Percent Due 2029
Contingencies and commitments
Liability as co-issuer	$ 825.0	$ 825.0

Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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