Goodwill and Intangible Assets (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Goodwill by segment
Goodwill	$ 840,287	$ 563,146
Crude oil logistics
Goodwill by segment
Goodwill	302,000	244,073
Water services
Goodwill by segment
Goodwill	338,842	119,668
Natural gas liquids logistics
Goodwill by segment
Goodwill	87,136	87,136
Retail propane
Goodwill by segment
Goodwill	$ 112,309	$ 112,269

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details