Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The amount of the obligation to return cash collateral or right to reclaim cash collateral under master netting arrangements.

+ References

No definition available.

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- Definition

Represents the fair value as of the balance sheet date of price risk derivative assets, net of price risk derivative liabilities and margin deposits, which includes all such derivative instruments that are recognized on the balance sheet.

+ References

No definition available.

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959

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- Definition

Fair value as of the balance sheet date of price risk derivative assets, net of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611

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Fair Value of Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Derivative contract information
Fair Value of Net Assets (Liabilities)	$ 56,363		$ 56,363		$ 8,034	$ (5,746)
Net cash collateral provided (held)	(13,704)		(13,704)		456	(1,360)
Net fair value of commodity derivatives on condensed consolidated balance sheet	42,659		42,659		8,490	(7,106)
Cross-commodity
Derivative contract information
Total Notional Units (Barrels)	(12,000)		(12,000)		140,000	430,000
Fair Value of Net Assets (Liabilities)	(1,283)		(1,283)		(1,876)	(10,208)
Crude oil fixed-price
Derivative contract information
Total Notional Units (Barrels)	(1,638,000)		(1,638,000)		(1,600,000)	(144,000)
Fair Value of Net Assets (Liabilities)	9,380		9,380		(2,796)	1,033
Crude oil index
Derivative contract information
Total Notional Units (Barrels)	2,195,000		2,195,000		3,598,000	(91,000)
Fair Value of Net Assets (Liabilities)	4,397		4,397		6,099	153
Propane fixed-price
Derivative contract information
Total Notional Units (Barrels)	1,238,000		1,238,000		60,000	(282,000)
Fair Value of Net Assets (Liabilities)	53		53		1,753	3,197
Refined products fixed-price
Derivative contract information
Total Notional Units (Barrels)	(4,475,000)		(4,475,000)		732,000
Fair Value of Net Assets (Liabilities)	38,712		38,712		560
Renewable Products
Derivative contract information
Total Notional Units (Barrels)	(14,000)		(14,000)		106,000
Fair Value of Net Assets (Liabilities)	5,104		5,104		4,084
Other
Derivative contract information
Total Notional Units (Barrels)						8,000
Fair Value of Net Assets (Liabilities)					210	79
Commodity contracts
Derivative contract information
Net gains (losses) on derivatives	55,981	(10,672)	38,496	(17,881)	(43,655)	(4,381)	5,676
Natural gas fixed-price
Derivative contract information
Fair Value of Net Assets (Liabilities)					$ 210