Condensed Consolidating Guarantor and Non-Guarantor Financial Information (Details 4) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ 81,829	$ 9,206
INVESTING ACTIVITIES:
Purchases of long-lived assets	(122,110)	(48,867)
Acquisitions of businesses, including acquired working capital, net of cash acquired	(63,898)	(15,869)
Cash flows from commodity derivatives	(21,693)	(9,967)
Proceeds from sales of assets	1,931	989
Investments in unconsolidated entities	(2,149)	(4,094)
Distributions of capital from unconsolidated entities	3,156
Loan for facility under construction	(3,913)
Payment on loan for facility under construction	1,600
Loan to affiliate	(15,621)
Net cash used in investing activities	(222,697)	(77,808)
FINANCING ACTIVITIES:
Proceeds from borrowings under revolving credit facilities	721,200	494,500
Payments on revolving credit facilities	(498,200)	(681,000)
Payments on other long-term debt	(1,629)	(2,347)
Debt issuance costs	(6)	(2,194)
Contributions from general partner	11	352
Contributions from noncontrolling interest owners	3,947
Distribution to partners	(73,097)	(49,491)
Distributions to noncontrolling interest owners	(9,057)	(12)
Proceeds from sale of common units, net of offering costs		338,033
Other	(98)
Net cash provided by financing activities	143,071	97,841
Net increase (decrease) in cash and cash equivalents	2,203	29,239
Cash and cash equivalents, beginning of period	41,303	10,440
Cash and cash equivalents, end of period	43,506	39,679
Reportable Entity | NGL Energy Partners LP (Parent)
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	(20,028)	(19,540)
FINANCING ACTIVITIES:
Debt issuance costs	54	(576)
Contributions from general partner	11	352
Distribution to partners	(73,097)	(49,491)
Proceeds from sale of common units, net of offering costs		338,033
Net changes in advances with consolidated entities	86,638	(238,560)
Net cash provided by financing activities	13,606	49,758
Net increase (decrease) in cash and cash equivalents	(6,422)	30,218
Cash and cash equivalents, beginning of period	29,115	1,181
Cash and cash equivalents, end of period	22,693	31,399
Reportable Entity | Guarantor Subsidiaries
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	93,216	26,650
INVESTING ACTIVITIES:
Purchases of long-lived assets	(100,508)	(48,608)
Acquisitions of businesses, including acquired working capital, net of cash acquired	(63,898)	(15,619)
Cash flows from commodity derivatives	(21,693)	(9,967)
Proceeds from sales of assets	1,931	989
Investments in unconsolidated entities	(2,149)	(4,094)
Distributions of capital from unconsolidated entities	3,156
Loan for facility under construction	(3,913)
Payment on loan for facility under construction	1,600
Loan to affiliate	(15,621)
Net cash used in investing activities	(201,095)	(77,299)
FINANCING ACTIVITIES:
Proceeds from borrowings under revolving credit facilities	704,000	494,500
Payments on revolving credit facilities	(488,000)	(681,000)
Payments on other long-term debt	(1,599)	(2,345)
Debt issuance costs	(60)	(1,618)
Net changes in advances with consolidated entities	(102,549)	239,973
Other	(28)
Net cash provided by financing activities	111,764	49,510
Net increase (decrease) in cash and cash equivalents	3,885	(1,139)
Cash and cash equivalents, beginning of period	9,757	8,728
Cash and cash equivalents, end of period	13,642	7,589
Reportable Entity | Non-Guarantor Subsidiaries
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	8,641	2,096
INVESTING ACTIVITIES:
Purchases of long-lived assets	(21,602)	(259)
Acquisitions of businesses, including acquired working capital, net of cash acquired		(250)
Net cash used in investing activities	(21,602)	(509)
FINANCING ACTIVITIES:
Proceeds from borrowings under revolving credit facilities	17,200
Payments on revolving credit facilities	(10,200)
Payments on other long-term debt	(30)	(2)
Contributions from noncontrolling interest owners	3,947
Distributions to noncontrolling interest owners	(9,057)	(12)
Net changes in advances with consolidated entities	15,911	(1,413)
Other	(70)
Net cash provided by financing activities	17,701	(1,427)
Net increase (decrease) in cash and cash equivalents	4,740	160
Cash and cash equivalents, beginning of period	2,431	531
Cash and cash equivalents, end of period	$ 7,171	$ 691