Acquisitions and dispositions - Dispositions (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on asset sales and disposals	$ 6,618	$ (1,831)	$ (7,924)
Proceeds from sale of assets	2,914	5,295	4,472
Promissory note	415	19,765
Property And Equipment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on asset sales and disposals	6,618	(1,831)	(7,924)
Ferrellgas, L.P. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on asset sales and disposals	6,618	(1,831)	(7,924)
Proceeds from sale of assets	$ 2,914	5,295	$ 4,472
Notes Receivable, Related Parties, Noncurrent		$ 17,001

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due after 1 year (or 1 business cycle).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
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