Business Combinations (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015	Jun. 24, 2016
Propane and related equipment sales [Member]
Aggregate fair value of transactions	$ 4,395	$ 6,602	$ 7,731
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		249
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	1,220	3,625	236
Payments to Acquire Businesses, Gross	3,539	4,476	4,250
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	0	0	3,000
Issuance of liabilities and other costs and considerations	856	2,126	481
Business Combination, Consideration Transferred	4,395	6,602	7,731
Propane and related equipment sales [Member] \| Ferrellgas, L.P. [Member]
Aggregate fair value of transactions	4,395	6,602	7,731
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		249
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	1,220	3,625	236
Payments to Acquire Businesses, Gross	3,539	4,476	4,250
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	0	0	3,000
Issuance of liabilities and other costs and considerations	856	2,126	481
Business Combination, Consideration Transferred	4,395	6,602	7,731
Midstream Operations - Water Solutions [Member]
Aggregate fair value of transactions			74,677
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			1,704
Payments to Acquire Businesses, Gross			74,677
Business Combination, Prior Period Adjustment, Working Capital			1,400
Midstream Operations - Water Solutions [Member] \| Ferrellgas, L.P. [Member]
Aggregate fair value of transactions			74,677
Payments to Acquire Businesses, Gross			74,677
Business Combination, Prior Period Adjustment, Working Capital			1,400
Midstream - Crude Oil Logistics [Member]
Aggregate fair value of transactions		10,700		$ 822,452
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		(600)		8,315
Finite-lived Intangible Assets Acquired		700
Postconfirmation, Goodwill		1,400		189,196
Payments to Acquire Businesses, Gross			560,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable			260,000
Issuance of liabilities and other costs and considerations			2,500
Business Combination, Consideration Transferred			822,500
Business Combination, Separately Recognized Transactions, Expenses and Losses Recognized	0	99	16,373
Midstream - Crude Oil Logistics [Member] \| Ferrellgas, L.P. [Member]
Aggregate fair value of transactions		10,700		822,452
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		(600)		8,315
Finite-lived Intangible Assets Acquired		700
Postconfirmation, Goodwill		1,400		$ 189,196
Payments to Acquire Businesses, Gross			560,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable			260,000
Issuance of liabilities and other costs and considerations			2,500
Business Combination, Consideration Transferred			822,500
Business Combination, Separately Recognized Transactions, Expenses and Losses Recognized	$ 0	100	$ 16,373
Property And Equipment [Member] \| Midstream - Crude Oil Logistics [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		9,200
Property And Equipment [Member] \| Midstream - Crude Oil Logistics [Member] \| Ferrellgas, L.P. [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		$ 9,200

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

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Business Combination, Prior Period Adjustment, Working Capital

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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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.

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- Definition

The expenses and losses recorded for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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

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Amount of goodwill at the balance sheet date after fresh-start adjustments.

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