Income (Loss) Per Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Income (Loss) Per Common Unit
Income (loss) from continuing operations	$ 49,106	$ 97,199	$ 42,464	$ (137,323)
Less: Continuing operations loss attributable to noncontrolling interests	166	307	563	1,170
Net income (loss) from continuing operations attributable to NGL Energy Partners LP	49,272	97,506	43,027	(136,153)
Less: Distributions to preferred unitholders (1)	(20,312)	(29,748)	(166,835)	(73,882)
Less: Continuing operations net (income) loss allocated to general partner (2)	(65)	(102)	16	107
NET INCOME (LOSS) FROM CONTINUING OPERATIONS ALLOCATED TO COMMON UNITHOLDERS (NOTE 3)	28,895	67,656	(123,792)	(209,928)
(Loss) income from discontinued operations, net of tax	(6,115)	13,329	(192,800)	433,501
Net loss attributable to redeemable noncontrolling interest	0	0	0	446
Less: Discontinued operations loss (income) allocated to general partner (2)	6	(13)	193	(434)
NET (LOSS) INCOME FROM DISCONTINUED OPERATIONS ALLOCATED TO COMMON UNITHOLDERS (NOTE 3)	(6,109)	13,316	(192,607)	433,513
NET INCOME (LOSS) ALLOCATED TO COMMON UNITHOLDERS	$ 22,786	$ 80,972	$ (316,399)	$ 223,585
BASIC INCOME (LOSS) PER COMMON UNIT
Income (Loss) From Continuing Operations	$ 0.23	$ 0.54	$ (0.97)	$ (1.71)
(Loss) Income From Discontinued Operations, net of Tax	(0.05)	0.11	(1.52)	3.53
Net Income (Loss)	0.18	0.65	(2.49)	1.82
DILUTED INCOME (LOSS) PER COMMON UNIT
Income (Loss) From Continuing Operations	0.22	0.53	(0.97)	(1.71)
(Loss) Income From Discontinued Operations, net of Tax	(0.05)	0.11	(1.52)	3.53
Net Income (Loss)	$ 0.18	$ 0.64	$ (2.49)	$ 1.82
Basic weighted average common units outstanding (in units)	128,201,369	123,892,680	127,026,510	122,609,625
Diluted weighted average common units outstanding (in units)	129,358,590	125,959,751	127,026,510	122,609,625
Common units
BASIC INCOME (LOSS) PER COMMON UNIT
Income (Loss) From Continuing Operations	$ 0.23	$ 0.54	$ (0.97)	$ (1.71)
(Loss) Income From Discontinued Operations, net of Tax	(0.05)	0.11	(1.52)	3.53
Net Income (Loss)	0.18	0.65	(2.49)	1.82
DILUTED INCOME (LOSS) PER COMMON UNIT
Income (Loss) From Continuing Operations	0.22	0.53	(0.97)	(1.71)
(Loss) Income From Discontinued Operations, net of Tax	(0.05)	0.11	(1.52)	3.53
Net Income (Loss)	$ 0.18	$ 0.64	$ (2.49)	$ 1.82
Basic weighted average common units outstanding (in units)	128,201,369	123,892,680	127,026,510	122,609,625
Diluted weighted average common units outstanding (in units)	129,358,590	125,959,751	127,026,510	122,609,625
Warrant \| Common units
DILUTED INCOME (LOSS) PER COMMON UNIT
Weighted average number of diluted units outstanding adjustment	0	1,456,947	0	0
Restricted units \| Common units
DILUTED INCOME (LOSS) PER COMMON UNIT
Weighted average number of diluted units outstanding adjustment	1,157,221	610,124	0	0

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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