Condensed parent only debtor in possession financial information - Cash flows (Details) - USD ($) $ in Thousands	6 Months Ended
Jan. 31, 2021	Jan. 31, 2020
Cash flows from operating activities:
Net cash provided by (used in) operating activities	$ 44,451	$ 568
Cash flows from investing activities:
Net cash used in investing activities	(32,189)	(48,541)
Cash flows from financing activities:
Net cash provided by (used in) financing activities	(19,540)	50,625
Increase (decrease) in cash and cash equivalents	(7,278)	2,652
Cash and cash equivalents - beginning of year	333,761	11,054
Cash, cash equivalents and restricted cash - end of year	326,483	$ 13,706
Debtor In Possession [Member]
Cash flows from financing activities:
Proceeds from loan from Ferrellgas, L.P.	19,900
Net cash provided by (used in) financing activities	19,900
Increase (decrease) in cash and cash equivalents	19,900
Cash and cash equivalents - beginning of year	6
Cash, cash equivalents and restricted cash - end of year	$ 19,906

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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