Consolidated Statements Of Partners' Capital (Deficit) - USD ($)	Total	Accumulated Other Comprehensive Income (Loss)	Total Ferrellgas Partners, L.P. Partners' Capital (Deficit) [Member]	Non-Controlling Interest [Member]	Common Unitholders [Member]	General Partner Unitholder [Member]	Ferrellgas Partners Finance Corp. [Member]	Ferrellgas Partners Finance Corp. [Member] Common Stock [Member]	Ferrellgas Partners Finance Corp. [Member] Additional Paid-in Capital [Member]	Ferrellgas Partners Finance Corp. [Member] Accumulated deficit [Member]	Ferrellgas, L.P. [Member]	Ferrellgas, L.P. [Member] Accumulated Other Comprehensive Income (Loss)	Ferrellgas, L.P. [Member] Common Unitholders [Member]	Ferrellgas, L.P. [Member] General Partner Unitholder [Member]	Ferrellgas Finance Corp. [Member]	Ferrellgas Finance Corp. [Member] Common Stock [Member]	Ferrellgas Finance Corp. [Member] Additional Paid-in Capital [Member]	Ferrellgas Finance Corp. [Member] Accumulated deficit [Member]
Partners' capital balance (in shares) at Jul. 31, 2014					81,228,200	820,500
Partners' capital balance at Jul. 31, 2014	$ (111,646,000)	$ 6,181,000	$ (112,366,000)	$ 720,000	$ (57,893,000)	$ (60,654,000)					$ 69,925,000	$ 6,258,000	$ 63,024,000	$ 643,000
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	50,695,000		50,183,000	512,000	49,681,000	502,000					50,695,000		50,183,000	512,000
Distributions	(173,244,000)		(167,105,000)	(6,139,000)	$ (165,433,000)	$ (1,672,000)					(607,875,000)		(601,736,000)	(6,139,000)
Common units issued in connection with acquisitions - shares					11,334,200	114,500
Issuance of common units in connection with acquisitions	265,639,000		265,608,000	31,000	$ 262,952,000	$ 2,656,000					833,875,000		825,452,000	8,423,000
Exercise of common unit options - shares					5,800	100
Exercise of common unit options - value	92,000		92,000	0	$ 91,000	$ 1,000
Common units issued in offering, net of issuance costs - shares					7,808,600	78,900
Common units issued in offering, net of issuance costs - value	191,660,000		182,837,000	8,823,000	$ 181,008,000	$ 1,829,000
Net earnings (loss)	30,089,000		29,620,000	469,000	$ 29,324,000	$ 296,000	$ (2,348)		$ 0	$ (2,348)	46,427,000		(45,958,000)	(469,000)	$ (4,108)		$ 0	$ (4,108)
Other comprehensive income (loss)	(45,576,000)	(45,115,000)	(45,115,000)	(461,000)							(45,576,000)	(45,576,000)
Partners' capital balance (in shares) at Jul. 31, 2015					100,376,800	1,014,000
Partners' capital balance at Jul. 31, 2015	207,709,000	(38,934,000)	203,754,000	3,955,000	$ 299,730,000	$ (57,042,000)					390,126,000	(39,318,000)	425,105,000	4,339,000
Stockholders' equity balance (in shares) at Jul. 31, 2014								1,000								1,000
Stockholders' equity balance at Jul. 31, 2014							969	$ 1,000	15,106	(15,137)					1,100	$ 1,000	49,159	(49,059)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contribution							2,379		2,379	0					4,108		4,108	0
Cash contributed by Ferrellgas Partners and general partner											42,655,000		42,224,000	431,000
Stockholders' equity balance (in shares) at Jul. 31, 2015								1,000								1,000
Stockholders' equity balance at Jul. 31, 2015							1,000	$ 1,000	17,485	(17,485)					1,100	$ 1,000	53,267	(53,167)
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	36,919,000		36,546,000	373,000	36,181,000	365,000					36,919,000		36,546,000	373,000
Distributions	(206,883,000)		(204,160,000)	(2,723,000)	$ (202,118,000)	$ (2,042,000)					(269,541,000)		(266,818,000)	(2,723,000)
Common units issued in connection with acquisitions - shares					(2,385,700)	(24,200)
Issuance of common units in connection with acquisitions	(46,432,000)		(46,432,000)	0	$ (45,968,000)	$ (464,000)					(284,000)		(284,000)	0
Exercise of common unit options - shares					11,600	100
Exercise of common unit options - value	184,000		184,000	0	$ 182,000	$ 2,000
Net earnings (loss)	(672,035,000)		(665,415,000)	(6,620,000)	$ (658,761,000)	$ (6,654,000)	(2,262)		0	(2,262)	(655,391,000)		(648,771,000)	(6,620,000)	(7,053)		0	(7,053)
Other comprehensive income (loss)	28,758,000	28,466,000	28,466,000	292,000							28,758,000	28,758,000
Partners' capital balance (in shares) at Jul. 31, 2016					98,002,700	989,900
Partners' capital balance at Jul. 31, 2016	(651,780,000)	(10,468,000)	(647,057,000)	(4,723,000)	$ (570,754,000)	$ (65,835,000)					(469,413,000)	(10,560,000)	(454,222,000)	(4,631,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contribution							2,262		2,262	0					8,553		8,553	0
Stockholders' equity balance (in shares) at Jul. 31, 2016								1,000								1,000
Stockholders' equity balance at Jul. 31, 2016							1,000	$ 1,000	19,747	(19,747)					2,600	$ 1,000	61,820	(60,220)
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	18,386,000		18,201,000	185,000	18,018,000	183,000					18,386,000		18,201,000	185,000
Distributions	(80,783,000)		(79,733,000)	(1,050,000)	$ (78,936,000)	$ (797,000)					(119,879,000)		(118,829,000)	(1,050,000)
Partners' Capital Account, Units, Treasury Units Purchased					(850,000)	0
Partners' Capital Account, Treasury Units, Purchased	(15,851,000)		(15,851,000)	0	$ (15,851,000)	$ 0
Issuance of common units in connection with acquisitions											167,843,000		166,148,000	1,695,000
Net earnings (loss)	(54,501,000)		(54,207,000)	(294,000)	$ (53,665,000)	$ (542,000)	(5,308)		0	(5,308)	(29,059,000)		(28,765,000)	(294,000)	(5,516)		0	(5,516)
Other comprehensive income (loss)	25,324,000	25,069,000	25,069,000	255,000							25,324,000	25,324,000
Partners' capital balance (in shares) at Jul. 31, 2017					97,152,700	989,900
Partners' capital balance at Jul. 31, 2017	(757,510,000)	$ 14,601,000	(753,578,000)	(3,932,000)	$ (701,188,000)	$ (66,991,000)					$ (406,798,000)	$ 14,764,000	$ (417,467,000)	$ (4,095,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contribution							5,308		5,308	0					5,516		5,516	0
Cash contributed by Ferrellgas Partners and general partner	$ 1,695,000		$ 0	$ 1,695,000	$ 0	$ 0
Stockholders' equity balance (in shares) at Jul. 31, 2017								1,000								1,000
Stockholders' equity balance at Jul. 31, 2017							$ 1,000	$ 1,000	$ 25,055	$ (25,055)					$ 2,600	$ 1,000	$ 67,336	$ (65,736)