Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Total revenues (in dollars)	$ 5,380,526us-gaap_SalesRevenueNet	$ 3,975,935us-gaap_SalesRevenueNet	$ 2,743,445us-gaap_SalesRevenueNet	$ 1,593,937us-gaap_SalesRevenueNet	$ 1,385,957us-gaap_SalesRevenueNet	$ 1,617,613us-gaap_SalesRevenueNet	$ 1,338,208us-gaap_SalesRevenueNet	$ 1,135,510us-gaap_SalesRevenueNet	$ 326,436us-gaap_SalesRevenueNet	$ 9,029,140us-gaap_SalesRevenueNet	$ 2,979,894us-gaap_SalesRevenueNet	$ 9,699,274us-gaap_SalesRevenueNet	$ 4,417,767us-gaap_SalesRevenueNet	$ 1,310,473us-gaap_SalesRevenueNet
Total cost of sales	5,179,465us-gaap_CostOfGoodsAndServicesSold	3,764,744us-gaap_CostOfGoodsAndServicesSold	2,576,029us-gaap_CostOfGoodsAndServicesSold	1,488,850us-gaap_CostOfGoodsAndServicesSold	1,303,076us-gaap_CostOfGoodsAndServicesSold	1,481,890us-gaap_CostOfGoodsAndServicesSold	1,204,545us-gaap_CostOfGoodsAndServicesSold	1,053,690us-gaap_CostOfGoodsAndServicesSold	298,985us-gaap_CostOfGoodsAndServicesSold	8,713,518us-gaap_CostOfGoodsAndServicesSold	2,791,926us-gaap_CostOfGoodsAndServicesSold	9,132,699us-gaap_CostOfGoodsAndServicesSold	4,039,110us-gaap_CostOfGoodsAndServicesSold	1,217,023us-gaap_CostOfGoodsAndServicesSold
Net income (loss)	(15,879)	43,146	24,052	(932)	(17,508)	22,341	40,477	10,082	(24,710)	(55,789)	(18,440)	48,758	48,190	7,864
Net income (loss) attributable to parent equity (in dollars)	$ (19,224)us-gaap_IncomeLossAttributableToParent	$ 42,331us-gaap_IncomeLossAttributableToParent	$ 23,898us-gaap_IncomeLossAttributableToParent	$ (941)us-gaap_IncomeLossAttributableToParent	$ (17,633)us-gaap_IncomeLossAttributableToParent	$ 22,341us-gaap_IncomeLossAttributableToParent	$ 40,176us-gaap_IncomeLossAttributableToParent	$ 10,073us-gaap_IncomeLossAttributableToParent	$ (24,650)us-gaap_IncomeLossAttributableToParent	$ (59,199)us-gaap_IncomeLossAttributableToParent	$ (18,574)us-gaap_IncomeLossAttributableToParent	$ 47,655us-gaap_IncomeLossAttributableToParent	$ 47,940us-gaap_IncomeLossAttributableToParent	$ 7,876us-gaap_IncomeLossAttributableToParent
Common Units
Earnings (loss) per unit, basic and diluted -
Earnings (loss) per unit, basic and diluted -	$ (0.34)	$ 0.46	$ 0.27	$ (0.05)	$ (0.35)	$ 0.39	$ 0.75	$ 0.18	$ (0.76)	$ (0.93)	$ (0.37)	$ 0.51	$ 0.96	$ 0.32
Weighted average units outstanding (in shares)	88,331,653	73,421,309	67,941,726	58,909,389	47,703,313	47,665,015	46,364,381	44,831,836	26,529,133	81,267,742	53,336,969	61,970,471	41,353,574	15,169,983
Subordinated Units
Earnings (loss) per unit, basic and diluted -
Earnings (loss) per unit, basic and diluted -		$ 0.46	$ 0.23	$ (0.09)	$ (0.46)	$ 0.39	$ 0.75	$ 0.18	$ (0.77)			$ 0.32	$ 0.93	$ 0.58
Weighted average units outstanding (in shares)	5,919,346	5,919,346	5,919,346	5,919,346	5,919,346	5,919,346	5,919,346	5,919,346	5,919,346		5,919,346	5,919,346	5,919,346	5,175,384

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(a),(d))

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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