Debt - Components Of Long-Term Debt (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Jul. 31, 2019
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	$ 2,541,378	$ 2,113,276
Unamortized debt issuance expense	36,284	24,516
Less: current portion of long-term debt	359,050	631,756
Long-term debt	2,146,044	1,457,004
Fixed rate 6.5% Due 2021
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	500,000	500,000
Fixed rate 6.75% Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	500,000	500,000
Fixed rate 6.75% Due 2022
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	476,107	476,633
Fixed rate 8.625% Due 2020
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	357,000	355,681
Fixed rate 10.00% Due 2025
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt	703,719
Variable interest rate Term Loan Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt		275,000
Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	4,552	5,962
Ferrellgas, L.P. [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	2,184,378	1,757,595
Unamortized debt issuance expense	36,284	23,562
Less: current portion of long-term debt	2,050	277,029
Long-term debt	2,146,044	1,457,004
Ferrellgas, L.P. [Member] \| Fixed rate 6.5% Due 2021
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	500,000	500,000
Ferrellgas, L.P. [Member] \| Fixed rate 6.75% Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	500,000	500,000
Ferrellgas, L.P. [Member] \| Fixed rate 6.75% Due 2022
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	476,107	476,633
Ferrellgas, L.P. [Member] \| Fixed rate 10.00% Due 2025
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt	703,719
Ferrellgas, L.P. [Member] \| Variable interest rate Term Loan Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt		275,000
Ferrellgas, L.P. [Member] \| Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	$ 4,552	$ 5,962

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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