Schedule I Parent Only Statements - Balance Sheets (Details) - USD ($) $ in Thousands	Jul. 31, 2022	Jul. 31, 2021	Mar. 30, 2021	Jul. 31, 2020	Jul. 31, 2019
Assets [Abstract]
Cash and cash equivalents	$ 158,737	$ 281,952		$ 333,761	$ 11,054
Prepaid expenses and other current assets	30,764	39,092
Total assets	1,608,115	1,729,644
Liabilities and Equity [Abstract]
Current portion of long-term debt	1,792	1,670
Other current liabilities	218,610	246,000
Accrued interest	29,703	29,095
Long-term debt	1,450,016	1,444,890
Partners' deficit
General partner	(71,320)	(72,178)
Accumulated other comprehensive income	37,907	88,866
Total Ferrellgas Partners, L.P. deficit	(880,224)	(815,113)
Total liabilities and partners' deficit	$ 1,608,115	$ 1,729,644
Limited partner unitholders, units outstanding			97,152,665
General partner unitholder, units outstanding	49,496	49,496
Class A Limited Partner Units
Partners' deficit
Limited partners	$ (1,229,823)	$ (1,214,813)
Limited partner unitholders, units outstanding	4,857,605	4,857,605	4,857,605
Class B Limited Partner Units
Partners' deficit
Limited partners	$ 383,012	$ 383,012
Limited partner unitholders, units outstanding	1,300,000	1,300,000
Parent Company [Member]
Assets [Abstract]
Cash and cash equivalents	$ 271	$ 264		$ 6	$ 8
Prepaid expenses and other current assets	21	19
Total assets	292	283
Liabilities and Equity [Abstract]
Other current liabilities	277	17,219
Investment in Ferrellgas, L.P.	880,239	798,177
Partners' deficit
General partner	(71,320)	(72,178)
Accumulated other comprehensive income	37,907	88,866
Total Ferrellgas Partners, L.P. deficit	(880,224)	(815,113)
Total liabilities and partners' deficit	$ 292	$ 283
General partner unitholder, units outstanding	49,496	49,496
Parent Company [Member] | Class A Limited Partner Units
Partners' deficit
Limited partners	$ (1,229,823)	$ (1,214,813)
Limited partner unitholders, units outstanding	4,857,605	4,857,605
Parent Company [Member] | Class B Limited Partner Units
Partners' deficit
Limited partners	$ 383,012	$ 383,012
Limited partner unitholders, units outstanding	1,300,000	1,300,000