Unaudited Condensed Consolidating Guarantor and Non-Guarantor Financial Information - Unaudited Condensed Consolidating Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Unaudited Condensed Consolidating Statement of Operations
REVENUES	$ 6,654,634	$ 3,876,676	$ 12,499,068	$ 7,607,381
COST OF SALES	6,509,527	3,757,448	12,205,683	7,386,131
OPERATING COSTS AND EXPENSES:
Operating	60,309	47,792	116,571	95,628
General and administrative	39,369	21,158	61,759	43,543
Depreciation and amortization	52,750	53,595	104,795	106,012
Loss on disposal or impairment of assets, net	5,988	110,959	107,323	99,142
Revaluation of liabilities	0	5,600	800	5,600
Operating Loss	(13,309)	(119,876)	(97,863)	(128,675)
OTHER INCOME (EXPENSE):
Equity in earnings of unconsolidated entities	379	2,170	598	4,089
Interest expense	(41,358)	(50,118)	(87,626)	(99,222)
(Loss) gain on early extinguishment of liabilities, net	0	1,943	(137)	(1,338)
Other income (expense), net	1,471	1,637	(32,298)	3,370
Loss From Continuing Operations Before Income Taxes	(52,817)	(164,244)	(217,326)	(221,776)
INCOME TAX EXPENSE	(691)	(49)	(1,342)	(505)
Loss From Continuing Operations	(53,508)	(164,293)	(218,668)	(222,281)
Income (Loss) From Discontinued Operations, net of Tax	408,447	(9,286)	404,318	(15,005)
Net Income (Loss)	354,939	(173,579)	185,650	(237,286)
LESS: NET LOSS (INCOME) ATTRIBUTABLE TO NONCONTROLLING INTERESTS	518	(80)	863	(132)
LESS: NET LOSS ATTRIBUTABLE TO REDEEMABLE NONCONTROLLING INTERESTS	48	288	446	685
NET INCOME (LOSS) ATTRIBUTABLE TO NGL ENERGY PARTNERS LP	355,505	(173,371)	186,959	(236,733)
Reportable Entity | NGL Energy Partners LP (Parent)
OTHER INCOME (EXPENSE):
Interest expense	(29,485)	(37,219)	(58,985)	(75,590)
(Loss) gain on early extinguishment of liabilities, net		1,943	(137)	(1,338)
Loss From Continuing Operations Before Income Taxes	(29,485)	(35,276)	(59,122)	(76,928)
EQUITY IN NET INCOME (LOSS) OF CONSOLIDATED SUBSIDIARIES	384,990	(138,095)	246,081	(159,805)
Loss From Continuing Operations	355,505	(173,371)	186,959	(236,733)
Net Income (Loss)	355,505	(173,371)	186,959	(236,733)
NET INCOME (LOSS) ATTRIBUTABLE TO NGL ENERGY PARTNERS LP	355,505	(173,371)	186,959	(236,733)
Reportable Entity | Guarantor Subsidiaries
Unaudited Condensed Consolidating Statement of Operations
REVENUES	6,653,716	3,875,073	12,494,255	7,604,293
COST OF SALES	6,510,385	3,757,218	12,207,375	7,386,305
OPERATING COSTS AND EXPENSES:
Operating	58,269	47,418	112,441	94,643
General and administrative	39,180	21,096	61,228	43,400
Depreciation and amortization	50,543	53,042	99,674	104,532
Loss on disposal or impairment of assets, net	5,988	110,959	107,323	99,142
Revaluation of liabilities	800	5,600	800	5,600
Operating Loss	(11,449)	(120,260)	(94,586)	(129,329)
OTHER INCOME (EXPENSE):
Equity in earnings of unconsolidated entities	379	2,170	598	4,089
Interest expense	(11,874)	(12,899)	(28,641)	(23,632)
(Loss) gain on early extinguishment of liabilities, net		0		0
Other income (expense), net	1,483	1,841	(32,090)	3,759
Loss From Continuing Operations Before Income Taxes	(21,461)	(129,148)	(154,719)	(145,113)
INCOME TAX EXPENSE	(691)	(49)	(1,342)	(505)
EQUITY IN NET INCOME (LOSS) OF CONSOLIDATED SUBSIDIARIES	(1,373)	(138)	(3,020)	(509)
Loss From Continuing Operations	(23,525)	(129,335)	(159,081)	(146,127)
Income (Loss) From Discontinued Operations, net of Tax	408,515	(8,760)	405,162	(13,678)
Net Income (Loss)	384,990	(138,095)	246,081	(159,805)
NET INCOME (LOSS) ATTRIBUTABLE TO NGL ENERGY PARTNERS LP	384,990	(138,095)	246,081	(159,805)
Reportable Entity | Non-Guarantor Subsidiaries
Unaudited Condensed Consolidating Statement of Operations
REVENUES	1,789	1,374	6,482	3,263
COST OF SALES	13	1	(23)	1
OPERATING COSTS AND EXPENSES:
Operating	2,040	374	4,130	985
General and administrative	189	62	531	143
Depreciation and amortization	2,207	553	5,121	1,480
Loss on disposal or impairment of assets, net	0	0	0	0
Revaluation of liabilities	(800)		0
Operating Loss	(1,860)	384	(3,277)	654
OTHER INCOME (EXPENSE):
Interest expense	(11)	(12)	(23)	(23)
Other income (expense), net	0	1	0	19
Loss From Continuing Operations Before Income Taxes	(1,871)	373	(3,300)	650
INCOME TAX EXPENSE	0	0	0	0
Loss From Continuing Operations	(1,871)	373	(3,300)	650
Income (Loss) From Discontinued Operations, net of Tax	(68)	(719)	(1,029)	(1,712)
Net Income (Loss)	(1,939)	(346)	(4,329)	(1,062)
NET INCOME (LOSS) ATTRIBUTABLE TO NGL ENERGY PARTNERS LP	(1,939)	(346)	(4,329)	(1,062)
Consolidating Adjustments
Unaudited Condensed Consolidating Statement of Operations
REVENUES	(871)	229	(1,669)	(175)
COST OF SALES	(871)	229	(1,669)	(175)
OTHER INCOME (EXPENSE):
Interest expense	12	12	23	23
Other income (expense), net	(12)	(205)	(208)	(408)
Loss From Continuing Operations Before Income Taxes	0	(193)	(185)	(385)
EQUITY IN NET INCOME (LOSS) OF CONSOLIDATED SUBSIDIARIES	(383,617)	138,233	(243,061)	160,314
Loss From Continuing Operations	(383,617)	138,040	(243,246)	159,929
Income (Loss) From Discontinued Operations, net of Tax	0	193	185	385
Net Income (Loss)	(383,617)	138,233	(243,061)	160,314
LESS: NET LOSS (INCOME) ATTRIBUTABLE TO NONCONTROLLING INTERESTS	518	(80)	863	(132)
LESS: NET LOSS ATTRIBUTABLE TO REDEEMABLE NONCONTROLLING INTERESTS	48	288	446	685
NET INCOME (LOSS) ATTRIBUTABLE TO NGL ENERGY PARTNERS LP	$ (383,051)	$ 138,441	$ (241,752)	$ 160,867