Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
OIL AND NATURAL GAS SALES (NOTE 3)	$ 103,768	$ 68,539	$ 294,555	$ 197,655
EXPENSES
Operating	27,321	25,638	78,466	62,453
Transportation	6,038	5,773	19,472	24,318
Depletion, depreciation and accretion (Note 3)	34,492	35,729	92,729	104,525
Asset impairment (Notes 3 and 4)	787	319,974	1,239	469,715
General and administrative (Note 3)	8,651	5,592	26,876	20,614
Severance	1,164	0	1,164	1,299
Transaction	0	6,088	0	7,325
Equity tax	0	0	1,224	3,053
Foreign exchange (gain) loss	(1,271)	(507)	779	1,059
Financial instruments loss (gain) (Note 10)	1,675	2,051	(5,211)	1,824
Interest expense (Note 5)	3,989	5,122	10,415	7,842
EXPENSES	82,846	405,460	227,153	704,027
LOSS ON SALE OF BRAZIL BUSINESS UNIT (NOTE 4)	0	0	(9,076)	0
GAIN ON ACQUISITION	0	0	0	11,712
INTEREST INCOME	301	730	954	1,928
INCOME (LOSS) BEFORE INCOME TAXES (NOTE 3)	21,223	(336,191)	59,280	(492,732)
INCOME TAX EXPENSE (RECOVERY)
Current	4,333	3,879	13,522	11,680
Deferred	13,760	(110,451)	36,664	(166,202)
INCOME TAX EXPENSE (RECOVERY)	18,093	(106,572)	50,186	(154,522)
NET INCOME (LOSS) AND COMPREHENSIVE INCOME (LOSS)	$ 3,130	$ (229,619)	$ 9,094	$ (338,210)
NET INCOME (LOSS) PER SHARE - BASIC AND DILUTED (in dollars per share)	$ 0.01	$ (0.71)	$ 0.02	$ (1.11)
WEIGHTED AVERAGE SHARES OUTSTANDING - BASIC (in shares)	394,771,194	321,725,379	397,439,007	304,098,944
WEIGHTED AVERAGE SHARES OUTSTANDING - DILUTED (in shares)	394,774,953	321,725,379	397,450,637	304,098,944