Physical Delivery Contracts and Commodity Derivatives (Details Textual)	Sep. 30, 2014
Derivatives, Fair Value [Line Items]
Quantity
Weighted Average Price
Commodity Contract [Member] \| Oct - Dec 2015 [Member]
Derivatives, Fair Value [Line Items]
Quantity	1,000
Weighted Average Price	96.70

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

Name:	invest_DerivativeNonmonetaryNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant