Acquisitions (Details 11) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013
High Sierra, Pecos, Third Coast, OWL and Gavilon Energy acquisitions
Construction in progress
Revenues	$ 9,800,398	$ 5,697,988
Net income (loss)	798	(72,171)
High Sierra, Pecos, Third Coast, OWL and Gavilon Energy acquisitions \| Common Units
Construction in progress
Basic loss per unit (in dollars per share)	$ (0.18)	$ (0.95)
Diluted loss per unit (in dollars per share)	$ (0.18)	$ (0.95)
High Sierra, Pecos, Third Coast, OWL and Gavilon Energy acquisitions \| Subordinated Units
Construction in progress
Basic loss per unit (in dollars per share)	$ (0.18)	$ (0.95)
Diluted loss per unit (in dollars per share)	$ (0.18)	$ (0.95)
High Sierra, Pecos, Third Coast, OWL and Gavilon Energy acquisitions \| Limited Partners
Construction in progress
Net income (loss)	(14,446)	(75,251)
OWL
Construction in progress
Expense related to retirement of liability		$ 4,800

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Name Accounting Standards Codification

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

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