Property and Equipment Changes in Capitalized Exploratory Drilling Costs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2013 USD ($) Well
Number of Wells
Reclassification to wells, equipment and facilities based on the determination of proved reserves (in wells) | Well	(1)
Cost
Reclassification to wells, equipment and facilities based on the determination of proved reserves | $	$ (4,435)