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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount before tax of income (loss) from an individually significant component disposed of or held-for-sale including the portion attributable to the noncontrolling interest. Excludes discontinued operations.

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Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

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Acquisitions, dispositions and other significant transactions - Dispositions (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2018 USD ($) item	Jul. 31, 2020 USD ($)	Jul. 31, 2019 USD ($)	Jul. 31, 2018 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		$ 7,924	$ 10,968	$ 187,399
Number of terminals sold \| item	2
Proceeds from sale of assets		4,472	5,699	152,587
Promissory note		5,330	16,216
Bridger Environmental LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		0	0	4,002
Propane and related equipment sales [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 26,600
Loss on asset sales and disposals		0	0	15,194
Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of assets	8,000
Promissory note	8,500			8,500
Losses before tax				55,400
Losses before tax to parent				54,800
Trucking Water Disposal And Terminal Assets [Member] \| Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 57,000
Loss on asset sales and disposals		0	2,679	120,240
Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		7,924	8,289	11,201
Rail cars [Member] \| Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		0	0	36,762
Proceeds from sale of assets				$ 51,300
Number of rail cars sold	1,292			1,292
Ferrellgas, L.P. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		7,924	10,968	$ 187,399
Number of terminals sold \| item	2
Proceeds from sale of assets		4,472	5,699	152,587
Promissory note		5,330	16,216
Ferrellgas, L.P. [Member] \| Bridger Environmental LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		0	0	4,002
Ferrellgas, L.P. [Member] \| Propane and related equipment sales [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 26,600
Loss on asset sales and disposals		0	0	15,194
Ferrellgas, L.P. [Member] \| Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of assets	8,000
Promissory note	8,500			8,500
Losses before tax				55,400
Losses before tax to parent				54,800
Ferrellgas, L.P. [Member] \| Trucking Water Disposal And Terminal Assets [Member] \| Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 57,000
Loss on asset sales and disposals		0	2,679	120,240
Ferrellgas, L.P. [Member] \| Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		7,924	8,289	11,201
Ferrellgas, L.P. [Member] \| Rail cars [Member] \| Midstream Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on asset sales and disposals		$ 0	$ 0	36,762
Proceeds from sale of assets				$ 51,300
Number of rail cars sold	1,292			1,292