Derivative Financial Instruments Additional Information (Details)	Jun. 30, 2013 MBbls MMBTU
Derivatives in Place for Anticipated Production
Anticipated natural gas production hedged (MMBtu)	47,679,000
Anticipated crude oil production hedged (MBbls)	5,392

The quantity of future oil and gas production being hedged.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 360

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 12.D.3(b))

-URI http://asc.fasb.org/extlink&oid=27015634&loc=d3e516453-122869

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 12

-Section D

-Paragraph b

-Subsection 3

Name:	us-gaap_PortionOfFutureOilAndGasProductionBeingHedged
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	instant