The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Instruments and Hedging Activities - AOCI Rollforward (Details) $ in Thousands, MMBbls in Millions	3 Months Ended		6 Months Ended
	Jan. 31, 2019 USD ($)	Jan. 31, 2018 USD ($)	Jan. 31, 2019 USD ($) MMBbls	Jan. 31, 2018 USD ($)
Derivative [Line Items]
Partners' capital balance, beginning			$ (1,034,477)
Change in value of derivative	$ (21,080)	$ 1,072	(29,234)	$ 23,521
Reclassification of gains on derivatives to earnings, net	3,807	(9,743)	(626)	(13,692)
Partners' capital balance, ending	(1,083,350)		(1,083,350)
Reclassification of net losses to earnings during next 12 months			8,500
Gain (loss) on discontinuation of cash flow hedge due to forecasted transaction probable of not occurring, net			$ 0	0
Number of barrels of propane covered by cash flow hedges \| MMBbls			3.9
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Partners' capital balance, beginning			$ 20,560	14,648
Partners' capital balance, ending	(9,300)	24,477	(9,300)	24,477
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Partners' capital balance, beginning			(680,078)
Change in value of derivative	(21,080)	1,072	(29,234)	23,521
Reclassification of gains on derivatives to earnings, net	3,807	(9,743)	(626)	(13,692)
Partners' capital balance, ending	(727,011)		(727,011)
Reclassification of net losses to earnings during next 12 months			8,500
Gain (loss) on discontinuation of cash flow hedge due to forecasted transaction probable of not occurring, net			$ 0	0
Number of barrels of propane covered by cash flow hedges \| MMBbls			3.9
Ferrellgas, L.P. [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Partners' capital balance, beginning			$ 20,560	14,648
Partners' capital balance, ending	$ (9,300)	$ 24,477	(9,300)	24,477
Commodity Derivatives Propane [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Change in value of derivative			(29,234)	23,283
Reclassification of gains on derivatives to earnings, net			(626)	(14,018)
Commodity Derivatives Propane [Member] \| Ferrellgas, L.P. [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Change in value of derivative			(29,234)	23,283
Reclassification of gains on derivatives to earnings, net			$ (626)	(14,018)
Interest Rate Swap [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Change in value of derivative				238
Reclassification of gains on derivatives to earnings, net				326
Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Derivative [Line Items]
Change in value of derivative				238
Reclassification of gains on derivatives to earnings, net				$ 326