The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Derivative Instruments and Hedging Activities - Effect on Comprehensive Income and Change in FV (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative	$ 1,870	$ (159)	$ (27,364)	$ 23,362
Amount of gain (loss) reclassified from AOCI into income	(6,416)	6,568	(5,790)	20,260
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net				(1,293)
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative	1,870	(159)	(27,364)	23,362
Amount of gain (loss) reclassified from AOCI into income	(6,416)	6,568	(5,790)	20,260
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net				(1,293)
Commodity Derivatives Propane [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative	1,870	(169)	(27,364)	23,114
Commodity Derivatives Propane [Member] \| Ferrellgas, L.P. [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative	1,870	(169)	(27,364)	23,114
Interest Rate Swap [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative		10		248
Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member]
Derivative [Line Items]
Amount of gain (loss) recognized in AOCI(L) on derivative		10		248
Interest Expense [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into income		(60)		(386)
Interest Expense [Member] \| Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into income		(60)		(386)
Midstream Operations [Member] \| Cost of Sales [Member] \| Commodity Derivatives Crude Oil [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net				(3,470)
Midstream Operations [Member] \| Cost of Sales [Member] \| Commodity Derivatives Crude Oil [Member] \| Ferrellgas, L.P. [Member]
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net				(3,470)
Propane [Member] \| Cost of Sales [Member] \| Commodity Derivatives Propane [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into income	(6,416)	6,628	(5,790)	20,646
Propane [Member] \| Cost of Sales [Member] \| Commodity Derivatives Propane [Member] \| Ferrellgas, L.P. [Member]
Derivative [Line Items]
Amount of gain (loss) reclassified from AOCI into income	$ (6,416)	$ 6,628	$ (5,790)	$ 20,646