Litigation (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended		12 Months Ended
	Sep. 30, 2010	Aug. 31, 2010	Dec. 31, 2011	Feb. 14, 2011	Dec. 31, 2008
Litigation (Textual) [Abstract]
Conducted Remediation Program			3 years
Remediation program			$ 40
Financial compensation for purported damages on mining engineer's report					18,900
Assessment for purported unjust enrichment on mining engineer's report					8,400
Court order requiring the parties to provide their positions on damages within (in days)		45 days
Approximate damages on plaintiffs' submission, Maximum	76,000
Approximate damages on plaintiffs' submission, Minimum	16,000
Approximate unjust enrichment on plaintiffs' submission, Maximum	38,000
Approximate unjust enrichment on plaintiffs' submission, Minimum	5,000
Amount assessed in damages				8,600
Amount assessed for plaintiffs representatives				900
Additional amount assessed in punitive damages				$ 8,600
Public Apology Date within Judgment				15 days
Claims associated with Chevron complaint against Lago Agrio litigation			One through eight
Chevron claim for declaratory relief related to Lago Agrio litigation			Ninth
Proposed additional payment for plaintiff attorney fees as percentage of judgement			0.10%
MTBE [Member]
Loss Contingencies [Line Items]
Pending lawsuits and claims			8