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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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=35706170&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=35750535&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=35750535&loc=d3e13495-108611

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Fair Value of Financial Instruments (Details 2) item in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)	Mar. 31, 2015 USD ($) item
Derivative contract information
Fair Value of Net Assets (Liabilities)	$ 4,235		$ 86,009
Net cash collateral (held) provided	8,543		(53,681)
Net commodity derivatives in condensed consolidated balance sheet	12,778		32,328
Cross-commodity
Derivative contract information
Fair Value of Net Assets (Liabilities)	(1,320)		(105)
Crude oil fixed-price
Derivative contract information
Fair Value of Net Assets (Liabilities)	102		(171)
Crude oil index-price
Derivative contract information
Fair Value of Net Assets (Liabilities)	624		1,835
Propane fixed-price
Derivative contract information
Fair Value of Net Assets (Liabilities)	(3,973)		(2,842)
Refined products fixed-price
Derivative contract information
Fair Value of Net Assets (Liabilities)	5,391		84,996
Other.
Derivative contract information
Fair Value of Net Assets (Liabilities)	3,411		$ 2,296
Commodity contracts
Derivative contract information
Net gains (losses) on derivatives	$ (41,243)	$ (17,485)
Long \| Cross-commodity
Derivative contract information
Total Notional Units (Barrels) \| item	99		98
Long \| Crude oil index-price
Derivative contract information
Total Notional Units (Barrels) \| item	198		751
Long \| Propane fixed-price
Derivative contract information
Total Notional Units (Barrels) \| item	485		193
Short \| Crude oil fixed-price
Derivative contract information
Total Notional Units (Barrels) \| item	1,209		1,113
Short \| Refined products fixed-price
Derivative contract information
Total Notional Units (Barrels) \| item	2,667		3,005