Debt - Components Of Long-Term Debt (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Jul. 31, 2020	Jun. 07, 2020	Apr. 30, 2020	Jan. 31, 2017	Jun. 30, 2015	Jul. 31, 2014	Nov. 30, 2010
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	$ 2,540,150	$ 2,541,074
Unamortized debt issuance and other costs	(33,949)	(35,583)
Less: current portion of long-term debt	859,095	859,095
Long-term debt	1,647,106	1,646,396
Fixed Rate Six Point Five Zero Due Two Thousand Twenty One [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 500,000	$ 500,000
Interest rate, as a percent	6.50%	6.50%						6.50%
Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 500,000	$ 500,000
Interest rate, as a percent	6.75%	6.75%				6.75%
Fixed Rate Six Point Seven Five Due Two Thousand twenty Two [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 475,770	$ 475,937
Interest rate, as a percent	6.75%	6.75%					6.75%
Unamortized premium	$ 770	$ 937
Fixed rate, 8.625%, due 2020
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 357,000	$ 357,000
Interest rate, as a percent	8.625%	8.625%	8.625%		8.625%
Fixed rate 10.00% Due 2025
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt	$ 703,424	$ 703,573
Interest rate, as a percent	10.00%			10.00%
Unamortized premium	$ 3,424	3,573
Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	3,956	4,564
Unamortized discount	$ 449	$ 537
Debt, Weighted Average Interest Rate	9.70%	9.40%
Ferrellgas, L.P. [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Total long-term debt	$ 2,183,150	$ 2,184,074
Unamortized debt issuance and other costs	(33,949)	(35,583)
Less: current portion of long-term debt	502,095	502,095
Long-term debt	1,647,106	1,646,396
Ferrellgas, L.P. [Member] | Fixed Rate Six Point Five Zero Due Two Thousand Twenty One [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 500,000	$ 500,000
Interest rate, as a percent	6.50%	6.50%						6.50%
Ferrellgas, L.P. [Member] | Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 500,000	$ 500,000
Interest rate, as a percent	6.75%	6.75%				6.75%
Ferrellgas, L.P. [Member] | Fixed Rate Six Point Seven Five Due Two Thousand twenty Two [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	$ 475,770	$ 475,937
Interest rate, as a percent	6.75%	6.75%					6.75%
Unamortized premium	$ 770	$ 937
Ferrellgas, L.P. [Member] | Fixed rate, 8.625%, due 2020
Schedule of Capitalization, Long-term Debt [Line Items]
Unsecured senior notes	357,000
Interest rate, as a percent			8.625%
Ferrellgas, L.P. [Member] | Fixed rate 10.00% Due 2025
Schedule of Capitalization, Long-term Debt [Line Items]
Senior secured debt	$ 703,424	703,573
Interest rate, as a percent	10.00%			10.00%
Unamortized premium	$ 3,424	3,573
Ferrellgas, L.P. [Member] | Notes payable Due 2020 to 2029
Schedule of Capitalization, Long-term Debt [Line Items]
Notes payable	3,956	4,564
Unamortized discount	$ 449	$ 537
Debt, Weighted Average Interest Rate	9.70%	9.40%