Acquisitions, dispositions and other significant transactions - Acquisitions Funding (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Business Acquisition [Line Items]
Aggregate fair value of transactions	$ 15,200	$ 20,600	$ 4,400
Ferrellgas, L.P. [Member]
Business Acquisition [Line Items]
Aggregate fair value of transactions	15,200	20,600	4,400
Propane and related equipment sales
Business Acquisition [Line Items]
Cash payments, net of cash acquired	13,551	18,141	3,539
Issuance of liabilities and other costs and considerations	1,650	2,426	856
Aggregate fair value of transactions	15,201	20,567	4,395
Aggregate fair value of transactions	15,201	20,567	4,395
Propane and related equipment sales \| Ferrellgas, L.P. [Member]
Business Acquisition [Line Items]
Cash payments, net of cash acquired	13,551	18,141	3,539
Issuance of liabilities and other costs and considerations	1,650	2,426	856
Aggregate fair value of transactions	15,201	20,567	4,395
Aggregate fair value of transactions	$ 15,201	$ 20,567	$ 4,395

Business Acquisition Cost Of Acquired Entity Issuance Of Liabilities And Other Costs

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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