Condensed Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2014	Sep. 30, 2014
REVENUES:
Crude oil logistics	$ 2,111,143us-gaap_OilAndGasRevenue	$ 4,040,426us-gaap_OilAndGasRevenue
Water solutions	52,719ngl_WaterSolutionsRevenue	100,033ngl_WaterSolutionsRevenue
Liquids	539,753ngl_LiquidsRevenue	1,014,910ngl_LiquidsRevenue
Retail propane	68,358us-gaap_PropaneRevenue	146,260us-gaap_PropaneRevenue
Refined products and renewables	2,607,220ngl_RefinedProductsAndRenewablesRevenue	3,724,717ngl_RefinedProductsAndRenewablesRevenue
Other	1,333us-gaap_OtherSalesRevenueNet	2,794us-gaap_OtherSalesRevenueNet
Total Revenues	5,380,526us-gaap_SalesRevenueNet	9,029,140us-gaap_SalesRevenueNet
COST OF SALES:
Crude oil logistics	2,083,712us-gaap_CostOfServicesOilAndGas	3,981,351us-gaap_CostOfServicesOilAndGas
Water solutions	(9,439)us-gaap_WaterProductionCosts	1,134us-gaap_WaterProductionCosts
Liquids	514,064ngl_CostOfSalesLiquids	976,080ngl_CostOfSalesLiquids
Retail propane	39,894us-gaap_PropaneCosts	87,418us-gaap_PropaneCosts
Refined products and renewables	2,550,851	3,665,164
Other	383us-gaap_OtherUtilityCosts	2,371us-gaap_OtherUtilityCosts
Total Cost of Sales	5,179,465us-gaap_CostOfGoodsAndServicesSold	8,713,518us-gaap_CostOfGoodsAndServicesSold
OPERATING COSTS AND EXPENSES:
Operating	101,553us-gaap_OperatingCostsAndExpenses	169,421us-gaap_OperatingCostsAndExpenses
General and administrative	41,639us-gaap_GeneralAndAdministrativeExpense	69,512us-gaap_GeneralAndAdministrativeExpense
Depreciation and amortization	50,099us-gaap_DepreciationAndAmortization	89,474us-gaap_DepreciationAndAmortization
Operating Income (Loss)	7,770us-gaap_OperatingIncomeLoss	(12,785)us-gaap_OperatingIncomeLoss
OTHER INCOME (EXPENSE):
Earnings of unconsolidated entities	3,697	6,262
Interest expense	(28,651)us-gaap_InterestExpense	(49,145)us-gaap_InterestExpense
Other, net	(617)us-gaap_OtherNonoperatingIncomeExpense	(1,008)us-gaap_OtherNonoperatingIncomeExpense
Loss before Income Taxes	(17,801)	(56,676)
INCOME TAX (PROVISION) BENEFIT	1,922us-gaap_IncomeTaxExpenseBenefit	887us-gaap_IncomeTaxExpenseBenefit
Net Loss	(15,879)	(55,789)
LESS: NET INCOME ALLOCATED TO GENERAL PARTNER	(11,056)	(20,437)
LESS: NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	(3,345)	(3,410)
NET LOSS ALLOCATED TO LIMITED PARTNERS	(30,280)	(79,636)
Common Units
OTHER INCOME (EXPENSE):
NET LOSS ALLOCATED TO LIMITED PARTNERS	$ (30,280)	$ (75,623)
BASIC AND DILUTED LOSS PER COMMON UNIT (in dollars per unit)	$ (0.34)	$ (0.93)
BASIC AND DILUTED WEIGHTED AVERAGE UNITS OUTSTANDING:
COMMON UNITS OUTSTANDING (In shares)	88,331,653	81,267,742

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