Dispositions - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended				0 Months Ended	12 Months Ended			12 Months Ended		0 Months Ended		12 Months Ended
	Feb. 28, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Block 64 EPSA [Member]	May 17, 2011 Antelope Project [Member]	Dec. 31, 2013 Antelope Project [Member]	Dec. 31, 2012 Antelope Project [Member]	Dec. 31, 2011 Antelope Project [Member]	Dec. 31, 2013 Petroandina [Member]	Dec. 31, 2013 Harvest Vinccler S.C.A. [Member]	Dec. 16, 2013 Petrodelta, S.A. [Member]	Dec. 16, 2013 Harvest Holding [Member]	Dec. 31, 2013 Harvest Holding [Member] First Closing [Member]	Dec. 16, 2013 Harvest Holding [Member] First Closing [Member]	Dec. 16, 2013 Harvest Holding [Member] Second Closing [Member]	Dec. 16, 2013 Harvest Holding [Member] Petroandina [Member]	Dec. 16, 2013 Harvest Holding [Member] Harvest Vinccler S.C.A. [Member]
Discontinued Operations [Line Items]
Cash purchase price for share purchase agreement													$ 400,000,000		$ 125,000,000	$ 275,000,000
Percentage of equity interest											100.00%		80.00%		29.00%	51.00%
Loss on Sale of Interest in Harvest holding														23,000,000
Percentage of noncontrolling interest													49.00%				29.00%	20.00%
Partner interest in equity method investee												60.00%
Termination payment fees		3,000,000								9,600,000
Share purchase agreement expenses, maximum										4,000,000
Impaired carrying value					6,400,000
Farm-out agreement, working interest percentage	75.00%
Partners carried interest for the minimum exploratory work commitment	25.00%
Impairment expense		575,000	2,900,000	3,335,000
Settlement cost		2,000,000
Proceeds from sale of projects						217,800,000
Closed transaction to sell							May 17, 2011
Effective date of sale							Mar. 01, 2011
Expense related to settlement of royalty payments								100,000
Write-offs of notes receivable								5,200,000
Accounts payable - carry obligation								3,600,000
Accrued interest with note receivable									$ 3,300,000