Document and Entity Information - USD ($)	12 Months Ended
	Mar. 31, 2022	Jun. 01, 2022	Sep. 30, 2021
Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-35172
Entity Registrant Name	NGL Energy Partners LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	27-3427920
Entity Address, Address Line One	6120 South Yale Avenue, Suite 805
Entity Address, City or Town	Tulsa,
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	74136
City Area Code	(918)
Local Phone Number	481-1119
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Share Price			$ 2.37
Entity Public Float			$ 243,400,000
Entity Common Stock, Shares Outstanding		130,695,970
Entity Central Index Key	0001504461
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Auditor Name	GRANT THORNTON LLP
Auditor Location	Tulsa, Oklahoma
Auditor Firm ID	248
NEW YORK STOCK EXCHANGE, INC. | Common units
Entity Information
Title of 12(b) Security	Common units representing Limited Partner Interests
Trading Symbol	NGL
Security Exchange Name	NYSE
NEW YORK STOCK EXCHANGE, INC. | Class B Perpetual Preferred Units
Entity Information
Title of 12(b) Security	Fixed-to-floating rate cumulative redeemable perpetual preferred units
Trading Symbol	NGL-PB
Security Exchange Name	NYSE
NEW YORK STOCK EXCHANGE, INC. | Class C Perpetual Preferred Units
Entity Information
Title of 12(b) Security	Fixed-to-floating rate cumulative redeemable perpetual preferred units
Trading Symbol	NGL-PC
Security Exchange Name	NYSE