Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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-Name Regulation S-X (SX)

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

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-Name Accounting Standards Codification

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-Section 45

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- Definition

Amount of interest capitalized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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

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-Name Accounting Standards Codification

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Property, Plant and Equipment (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
Property, Plant and Equipment (Details) (USD $)	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Property, Plant and Equipment
Property, plant and equipment, gross	$ 1,586,370,000us-gaap_PropertyPlantAndEquipmentGross		$ 1,586,370,000us-gaap_PropertyPlantAndEquipmentGross		$ 938,910,000us-gaap_PropertyPlantAndEquipmentGross	$ 576,564,000us-gaap_PropertyPlantAndEquipmentGross
Less: Accumulated depreciation	(153,057,000)		(153,057,000)		(109,564,000)	(50,127,000)
Net property, plant and equipment	1,433,313,000us-gaap_PropertyPlantAndEquipmentNet		1,433,313,000us-gaap_PropertyPlantAndEquipmentNet		829,346,000us-gaap_PropertyPlantAndEquipmentNet	526,437,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	28,400,000us-gaap_Depreciation	13,700,000us-gaap_Depreciation	46,900,000us-gaap_Depreciation	27,200,000us-gaap_Depreciation	59,900,000us-gaap_Depreciation	39,200,000us-gaap_Depreciation	10,600,000us-gaap_Depreciation
Interest expense capitalized					700,000us-gaap_InterestCostsCapitalized
Natural gas liquids terminal assets
Property, Plant and Equipment
Property, plant and equipment, gross	127,258,000		127,258,000		75,141,000	63,637,000
Natural gas liquids terminal assets \| Minimum
Property, Plant and Equipment
Useful life			2 years		2 years
Natural gas liquids terminal assets \| Maximum
Property, Plant and Equipment
Useful life			30 years		30 years
Retail propane equipment
Property, Plant and Equipment
Property, plant and equipment, gross	167,825,000		167,825,000		160,758,000	152,802,000
Retail propane equipment \| Minimum
Property, Plant and Equipment
Useful life			2 years		2 years
Retail propane equipment \| Maximum
Property, Plant and Equipment
Useful life			30 years		30 years
Vehicles
Property, Plant and Equipment
Property, plant and equipment, gross					152,676,000	88,173,000
Vehicles \| Minimum
Property, Plant and Equipment
Useful life					3 years
Vehicles \| Maximum
Property, Plant and Equipment
Useful life					25 years
Water treatment facilities and equipment
Property, Plant and Equipment
Property, plant and equipment, gross	209,644,000		209,644,000		180,985,000	91,944,000
Water treatment facilities and equipment \| Minimum
Property, Plant and Equipment
Useful life			3 years		3 years
Water treatment facilities and equipment \| Maximum
Property, Plant and Equipment
Useful life			30 years		30 years
Crude oil tanks and related equipment
Property, Plant and Equipment
Property, plant and equipment, gross	145,287,000		145,287,000		106,125,000	22,577,000
Crude oil tanks and related equipment \| Minimum
Property, Plant and Equipment
Useful life			2 years		2 years
Crude oil tanks and related equipment \| Maximum
Property, Plant and Equipment
Useful life			40 years		40 years
Barges and towboats
Property, Plant and Equipment
Property, plant and equipment, gross	56,094,000		56,094,000		52,217,000	25,963,000
Barges and towboats \| Minimum
Property, Plant and Equipment
Useful life			5 years		5 years
Barges and towboats \| Maximum
Property, Plant and Equipment
Useful life			40 years		40 years
Information technology equipment
Property, Plant and Equipment
Property, plant and equipment, gross	30,519,000		30,519,000		20,768,000	12,169,000
Information technology equipment \| Minimum
Property, Plant and Equipment
Useful life			3 years		3 years
Information technology equipment \| Maximum
Property, Plant and Equipment
Useful life			7 years		7 years
Buildings and leasehold improvements
Property, Plant and Equipment
Property, plant and equipment, gross	77,415,000		77,415,000		60,004,000	48,975,000
Buildings and leasehold improvements \| Minimum
Property, Plant and Equipment
Useful life			3 years		3 years
Buildings and leasehold improvements \| Maximum
Property, Plant and Equipment
Useful life			40 years		40 years
Land
Property, Plant and Equipment
Property, plant and equipment, gross	88,350,000		88,350,000		30,241,000	21,815,000
Linefill and tank bottoms
Property, Plant and Equipment
Property, plant and equipment, gross					13,403,000
Other
Property, Plant and Equipment
Property, plant and equipment, gross	16,770,000		16,770,000		6,341,000	16,104,000
Other \| Minimum
Property, Plant and Equipment
Useful life			3 years		5 years
Other \| Maximum
Property, Plant and Equipment
Useful life			30 years		30 years
Construction in progress
Property, Plant and Equipment
Property, plant and equipment, gross	$ 57,319,000		$ 57,319,000		$ 80,251,000	$ 32,405,000