Property, Plant and Equipment (Details) (USD $)	3 Months Ended		6 Months Ended			6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended					6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2013	Sep. 30, 2013 Natural gas liquids terminal assets	Mar. 31, 2013 Natural gas liquids terminal assets	Sep. 30, 2013 Retail propane equipment	Mar. 31, 2013 Retail propane equipment	Sep. 30, 2013 Retail propane equipment Minimum	Mar. 31, 2013 Retail propane equipment Minimum	Sep. 30, 2013 Retail propane equipment Maximum	Mar. 31, 2013 Retail propane equipment Maximum	Sep. 30, 2013 Vehicles	Mar. 31, 2013 Vehicles	Sep. 30, 2013 Vehicles Minimum	Mar. 31, 2013 Vehicles Minimum	Sep. 30, 2013 Vehicles Maximum	Mar. 31, 2013 Vehicles Maximum	Sep. 30, 2013 Water treatment facilities and equipment	Mar. 31, 2013 Water treatment facilities and equipment	Sep. 30, 2013 Water treatment facilities and equipment Minimum	Mar. 31, 2013 Water treatment facilities and equipment Minimum	Sep. 30, 2013 Water treatment facilities and equipment Maximum	Mar. 31, 2013 Water treatment facilities and equipment Maximum	Sep. 30, 2013 Crude oil tanks and related equipment	Mar. 31, 2013 Crude oil tanks and related equipment	Sep. 30, 2013 Crude oil tanks and related equipment Minimum	Mar. 31, 2013 Crude oil tanks and related equipment Minimum	Sep. 30, 2013 Crude oil tanks and related equipment Maximum	Mar. 31, 2013 Crude oil tanks and related equipment Maximum	Sep. 30, 2013 Barges and towboats	Mar. 31, 2013 Barges and towboats	Sep. 30, 2013 Information technology equipment	Mar. 31, 2013 Information technology equipment	Sep. 30, 2013 Information technology equipment Minimum	Mar. 31, 2013 Information technology equipment Minimum	Sep. 30, 2013 Information technology equipment Maximum	Mar. 31, 2013 Information technology equipment Maximum	Sep. 30, 2013 Buildings and leasehold improvements	Mar. 31, 2013 Buildings and leasehold improvements	Sep. 30, 2013 Buildings and leasehold improvements Minimum	Mar. 31, 2013 Buildings and leasehold improvements Minimum	Sep. 30, 2013 Buildings and leasehold improvements Maximum	Mar. 31, 2013 Buildings and leasehold improvements Maximum	Sep. 30, 2013 Land	Mar. 31, 2013 Land	Sep. 30, 2013 Other	Mar. 31, 2013 Other	Sep. 30, 2013 Other Minimum	Mar. 31, 2013 Other Minimum	Sep. 30, 2013 Other Maximum	Mar. 31, 2013 Other Maximum	Sep. 30, 2013 Construction in progress	Mar. 31, 2013 Construction in progress
Property, Plant and Equipment
Useful life						30 years	30 years			5 years	5 years	20 years	20 years			5 years	5 years	10 years	10 years			3 years	3 years	30 years	30 years			2 years	2 years	30 years	30 years	20 years	20 years			3 years	3 years	5 years	5 years			5 years	5 years	30 years	30 years					3 years	3 years	10 years	10 years
Property, plant and equipment, gross	$ 708,053,000		$ 708,053,000		$ 567,064,000	$ 64,586,000	$ 63,637,000	$ 157,534,000	$ 152,802,000					$ 108,280,000	$ 85,200,000					$ 150,632,000	$ 91,601,000					$ 27,384,000	$ 21,308,000					$ 33,957,000	$ 21,135,000	$ 15,223,000	$ 12,169,000					$ 45,108,000	$ 48,394,000					$ 22,994,000	$ 21,604,000	$ 17,673,000	$ 17,288,000					$ 64,682,000	$ 31,926,000
Less: Accumulated depreciation	(76,390,000)		(76,390,000)		(50,127,000)
Net property, plant and equipment	631,663,000		631,663,000		516,937,000
Depreciation expense	$ 13,700,000	$ 7,700,000	$ 27,200,000	$ 13,800,000