Commitments and Contingencies (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net minimum commitments
Total	$ 29,016,000
2013	19,016,000
2014	1,948,000
2015	1,969,000
2016	2,010,000
2017 and beyond	4,073,000
Office rent	1,100,000	600,000	600,000
Drilling contracts
Net minimum commitments
Total	10,261,000
2013	10,261,000
Non-cancellable office lease commitments
Net minimum commitments
Total	11,723,000
2013	1,723,000
2014	1,948,000
2015	1,969,000
2016	2,010,000
2017 and beyond	4,073,000
Seismic contracts
Net minimum commitments
Total	6,698,000
2013	6,698,000
Other
Net minimum commitments
Total	334,000
2013	$ 334,000