Schedule I Parent Only Balance Sheets, Statements Of Earnings And Cash Flows (Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jul. 31, 2020	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Cash flows from operating activities:
Net loss	$ (70,605)	$ (15,471)	$ 48,791	$ (45,717)	$ (217,797)	$ 11,062	$ (1,774)	$ (48,316)	$ (83,002)	$ (64,545)	$ (256,825)
Reconciliation of net earnings to net cash used in operating activities:
Other									12,583	12,696	9,997
Net cash provided by (used in) operating activities									112,842	15,075	74,148
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired									(10,195)	(13,551)	(18,141)
Net cash used in investing activities									(71,296)	(124,327)	49,527
Cash flows from financing activities:
Distributions									0	(9,814)	(39,254)
Cash paid for financing costs and other									(29,458)	(548)	(18,535)
Proceeds from issuance of long-term debt									703,750	0	323,680
Payments on long-term debt									(285,857)	(2,428)	(212,920)
Net cash provided by (used in) financing activities									281,161	995	(10,124)
Increase (decrease) in cash and cash equivalents									322,707	(108,257)	113,551
Cash and cash equivalents - beginning of year				11,054				5,760	11,054	119,311	5,760
Cash, cash equivalents and restricted cash - end of year	333,761				119,311				333,761	11,054	119,311
Parent Company [Member]
Cash flows from operating activities:
Net loss									(82,499)	(64,247)	(254,581)
Reconciliation of net earnings to net cash used in operating activities:
Other									17,749	4,141	3,673
Equity in (earnings) loss of Ferrellgas, L.P.									49,261	29,219	219,902
Net cash provided by (used in) operating activities									(15,489)	(30,887)	(31,006)
Cash flows from investing activities:
Distributions received from Ferrellgas, L.P.									15,496	40,706	70,246
Net cash used in investing activities									15,496	40,706	70,246
Cash flows from financing activities:
Distributions										(9,814)	(39,254)
Cash paid for financing costs and other									(9)		(42)
Net cash provided by (used in) financing activities									(9)	(9,814)	(39,296)
Increase (decrease) in cash and cash equivalents									(2)	5	(56)
Cash and cash equivalents - beginning of year				$ 8				$ 59	8	3	59
Cash, cash equivalents and restricted cash - end of year	$ 6				$ 3				$ 6	$ 8	$ 3