ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Schedule of Changes in Accumulated Other Comprehensive Income Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, net of tax	$ (39,789)
Amounts reclassified from accumulated other comprehensive income:
Ending balance, net of tax	(637,282)	$ (39,789)
Cash Flow Hedges
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, net of tax	24,025	86,783	$ (1,395)
Other comprehensive income (loss) before reclassifications:
Change in fair value of derivatives	(1,648)	52,630	136,097
Foreign currency translations	0	0	0
Income tax effect	581	(19,096)	(48,995)
Net of tax	(1,067)	33,534	87,102
Amounts reclassified from accumulated other comprehensive income:
Income tax effect	(12,499)	(54,833)	606
Net of tax	22,958	96,292	(1,076)
Other comprehensive income (loss), net of tax	(24,025)	(62,758)	88,178
Ending balance, net of tax	0	24,025	86,783
Cash Flow Hedges | Operating revenue: oil/natural gas production
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	35,457	149,955	526
Cash Flow Hedges | Derivative income, net
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income		1,170	(2,208)
Cash Flow Hedges | Other operational expenses
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	0
Foreign Currency Items
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, net of tax	(6,073)	(3,468)	(667)
Other comprehensive income (loss) before reclassifications:
Change in fair value of derivatives	0	0	0
Foreign currency translations	(8)	(2,605)	(2,801)
Income tax effect	0	0	0
Net of tax	(8)	(2,605)	(2,801)
Amounts reclassified from accumulated other comprehensive income:
Income tax effect	0	0	0
Net of tax	(6,081)	0	0
Other comprehensive income (loss), net of tax	6,073	(2,605)	(2,801)
Ending balance, net of tax	0	(6,073)	(3,468)
Foreign Currency Items | Operating revenue: oil/natural gas production
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	0	0	0
Foreign Currency Items | Derivative income, net
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income		0	0
Foreign Currency Items | Other operational expenses
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	(6,081)
Total
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, net of tax	17,952	83,315	(2,062)
Other comprehensive income (loss) before reclassifications:
Change in fair value of derivatives	(1,648)	52,630	136,097
Foreign currency translations	(8)	(2,605)	(2,801)
Income tax effect	581	(19,096)	(48,995)
Net of tax	(1,075)	30,929	84,301
Amounts reclassified from accumulated other comprehensive income:
Income tax effect	(12,499)	(54,833)	606
Net of tax	16,877	96,292	(1,076)
Other comprehensive income (loss), net of tax	(17,952)	(65,363)	85,377
Ending balance, net of tax	0	17,952	83,315
Total | Operating revenue: oil/natural gas production
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	35,457	149,955	526
Total | Derivative income, net
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income		$ 1,170	$ (2,208)
Total | Other operational expenses
Amounts reclassified from accumulated other comprehensive income:
Reclassification from accumulated other comprehensive income	$ (6,081)