Document and Entity Information	6 Months Ended
Sep. 30, 2011	Nov. 11, 2011 Common units	Nov. 11, 2011 Subordinated units
Entity Registrant Name	NGL Energy Partners LP
Entity Central Index Key	0001504461
Document Type	10-Q
Document Period End Date	Sep. 30, 2011
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		21,796,253	5,919,346
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2

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