Goodwill (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011	Sep. 30, 2010	Sep. 30, 2010 NGL Supply	Mar. 31, 2010 NGL Supply	Mar. 31, 2013 Crude oil logistics	Mar. 31, 2013 Water services	Mar. 31, 2013 Retail propane	Mar. 31, 2012 Retail propane	Mar. 31, 2011 Retail propane	Sep. 30, 2010 Retail propane NGL Supply	Mar. 31, 2013 Natural gas liquids logistics	Mar. 31, 2012 Natural gas liquids logistics	Mar. 31, 2011 Natural gas liquids logistics	Sep. 30, 2010 Natural gas liquids logistics NGL Supply
Goodwill by segment
Goodwill	$ 563,146	$ 167,245	$ 8,568	$ 4,580	$ 4,580	$ 4,457	$ 244,073	$ 119,668	$ 112,269	$ 90,287	$ 6,534	$ 2,546	$ 87,136	$ 76,958	$ 2,034	$ 2,034

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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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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