Prepayment penalties will be incurred if debt is paid off prior to this date.

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Debt maturity year

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No definition available.

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Debt issued premium, percent of par

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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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- Definition

Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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No definition available.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Debt (Senior Notes Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Debt (Senior Notes Narrative) (Details) - USD ($)	Jul. 31, 2017	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015	Apr. 30, 2011	Apr. 30, 2010
Interest Paid		$ 143,441,000	$ 133,629,000	$ 91,783,000
Ferrellgas, L.P. [Member]
Interest Paid		$ 122,084,000	$ 117,931,000	$ 76,085,000
Fixed Rate Six Point Seven Five Due Two Thousand twenty Two [Domain]
Senior note, issuance date		Nov. 04, 2013
Debt instrument, face amount	$ 325,000,000	$ 325,000,000
Debt instrument, fixed interest rate	6.75%	6.75%
Proceeds from issuance of unsecured debt		$ 319,300,000
Debt Instrument, Maturity Date		Nov. 01, 2022
Debt issued premium, percent of par	104.00%	104.00%
Fixed Rate Six Point Seven Five Due Two Thousand twenty Two [Domain] \| Ferrellgas, L.P. [Member]
Senior note, issuance date		Nov. 04, 2013
Debt instrument, face amount	$ 325,000,000	$ 325,000,000
Debt instrument, fixed interest rate	6.75%	6.75%
Proceeds from issuance of unsecured debt		$ 319,300,000
Debt Instrument, Maturity Date		Nov. 01, 2022
Debt instrument prepayment penalty prior to date		2019
Debt issued premium, percent of par	104.00%	104.00%
Fixed Rate Six Point Five Zero Due Two Thousand Twenty One [Member]
Senior note, issuance date		Nov. 06, 2010
Debt instrument, face amount	$ 500,000,000.0	$ 500,000,000.0
Debt instrument, fixed interest rate	6.50%	6.50%
Debt Instrument, Frequency of Periodic Payment		semi-annually
Debt Instrument, Maturity Date		May 01, 2021
Debt instrument prepayment penalty prior to date		2019
Fixed Rate Six Point Five Zero Due Two Thousand Twenty One [Member] \| Ferrellgas, L.P. [Member]
Senior note, issuance date		Nov. 06, 2010
Debt instrument, face amount	$ 500,000,000.0	$ 500,000,000.0
Debt instrument, fixed interest rate	6.50%	6.50%
Debt Instrument, Frequency of Periodic Payment		semi-annually
Debt Instrument, Maturity Date		May 01, 2021
Debt instrument prepayment penalty prior to date		2019
Fixed Rate Nine Point One Two Five Percentage Due Two Thousand Seventeen [Member]
Senior note, issuance date		Jun. 06, 2014
Debt instrument, face amount	$ 150,000,000	$ 150,000,000
Debt instrument, fixed interest rate	9.125%	9.125%
Debt Instrument, Maturity Date		Oct. 01, 2017
Debt instrument prepayment penalty prior to date		2019
Debt Instrument, Repurchased Face Amount	$ 300,000,000	$ 300,000,000
Payment for Debt Extinguishment or Debt Prepayment Cost		14,700,000
Interest Paid		$ 3,300,000
Fixed Rate Nine Point One Two Five Percentage Due Two Thousand Seventeen [Member] \| Ferrellgas, L.P. [Member]
Senior note, issuance date		Jun. 06, 2014
Debt instrument, face amount	$ 150,000,000	$ 150,000,000
Debt instrument, fixed interest rate	9.125%	9.125%
Debt Instrument, Maturity Date		Oct. 01, 2017
Debt Instrument, Repurchased Face Amount	$ 300,000,000	$ 300,000,000
Payment for Debt Extinguishment or Debt Prepayment Cost		14,700,000
Interest Paid		$ 3,300,000
Fixed Rate Eight Point Six Two Five Due Two Thousand Twenty [Member]
Proceeds from Debt, Net of Issuance Costs	166,100,000
Senior note, issuance date		Jan. 24, 2017
Debt instrument, face amount	$ 175,000,000.0	$ 175,000,000.0				$ 280,000,000.0
Debt Instrument, Frequency of Periodic Payment		semi-annually
Debt instrument prepayment penalty prior to date		2018
Debt Instrument, Repurchased Face Amount					$ 98,000,000
Debt issued premium, percent of par	96.00%	96.00%
Fixed Rate Eight Point Six Two Five Due Two Thousand Twenty [Member] \| Ferrellgas, L.P. [Member]
Debt instrument, fixed interest rate	8.625%	8.625%
Debt instrument, maturity year		2020
Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Proceeds from Debt, Net of Issuance Costs		$ 491,300,000
Senior note, issuance date		Jun. 24, 2015
Debt instrument, face amount	$ 500,000,000	$ 500,000,000
Debt instrument, fixed interest rate	6.75%	6.75%
Debt Instrument, Frequency of Periodic Payment		semi-annually
Debt Instrument, Maturity Date		Jun. 15, 2023
Debt instrument prepayment penalty prior to date		2021
Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member] \| Ferrellgas, L.P. [Member]
Proceeds from Debt, Net of Issuance Costs		$ 491,300,000
Senior note, issuance date		Jun. 24, 2015
Debt instrument, face amount	$ 500,000,000	$ 500,000,000
Debt instrument, fixed interest rate	6.75%	6.75%
Debt Instrument, Frequency of Periodic Payment		semi-annually
Debt Instrument, Maturity Date		Jun. 15, 2023
Debt instrument prepayment penalty prior to date		2021