Supplemental Information On Oil And Gas Exploration And Production Activities (Unaudited) - Schedule of Changes in Proved Undeveloped Reserves (Details)	12 Months Ended
	Dec. 31, 2016 MBoe
Extractive Industries [Abstract]
Proved undeveloped reserves at December 31, 2015	3,961
Conversions to developed	(169)
Extensions and discoveries	293
Purchases	873
Revisions	(2,268)
Proved undeveloped reserves at December 31, 2016	2,690