Debt - Components Of Long-Term Debt (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jul. 31, 2018
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	$ 2,113,276	$ 2,111,830
Unamortized Debt Issuance Expense	(24,516)	(30,791)
Less: current portion of long-term debt	631,756	2,402
Long-term debt	1,457,004	2,078,637
Fixed Rate 6.5% Due 2021
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	500,000	500,000
Fixed Rate 6.75% Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	500,000	500,000
Fixed Rate 6.75% Due 2022
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	476,633	477,375
Fixed Rate 8.625% Due 2020
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	355,681	353,234
Variable interest Term Loan Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured term loan	275,000	275,000
Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	5,962	6,221
Ferrellgas, L.P. [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	1,757,595	1,758,596
Unamortized Debt Issuance Expense	(23,562)	(28,057)
Less: current portion of long-term debt	277,029	2,402
Long-term debt	1,457,004	1,728,137
Ferrellgas, L.P. [Member] \| Fixed Rate 6.5% Due 2021
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	500,000	500,000
Ferrellgas, L.P. [Member] \| Fixed Rate 6.75% Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	500,000	500,000
Ferrellgas, L.P. [Member] \| Fixed Rate 6.75% Due 2022
Schedule of Capitalization, Long-term Debt [Line Items]
Senior notes	476,633	477,375
Ferrellgas, L.P. [Member] \| Variable interest Term Loan Due 2023
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured term loan	275,000	275,000
Ferrellgas, L.P. [Member] \| Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	$ 5,962	$ 6,221

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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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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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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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