Contingencies and litigations (Details) (USD $)	Mar. 31, 2013	Feb. 15, 2013	Feb. 14, 2012	Mar. 31, 2011	Dec. 31, 2009	Jan. 31, 2006
Acutal damages found by jury in millions	0	0	0	0	66.5	0
Actual damages in tortous interference claim millions	0	0	0	0	31.16	0
Exemplary damages and individual and Eurenergy millions	0	0	0	0	8.5	0
Reinstated the jury award of actual damages jointly and severely against The individual and EurEnergy millions	0	0	66.5	0	0	0
Joint operating agreement evidencing its acquisition of a interest	0.00%	0.00%	0.00%	0.00%	0.00%	5.00%
Received an invoice from Chesapeake	$ 0	$ 0	$ 0	$ 0	$ 0	$ 556,217
Chesapeake received a summary judgment award	0	0	0	686,874	0	0
Legal Fee payable	0	0	0	65,000	0	0
Appealed the judgment to the Court of Appeals which reduced the judgment by approximately	0	16,000	0	0	0	0
Recorded a liability due Chesapeake.	$ 491,000	$ 0	$ 0	$ 0	$ 0	$ 0