OTHER SUPPLEMENTAL INFORMATION (Schedule of Accounts Payable and Accrued Liabilities- Third Party) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Other Supplemental Information Disclosure [Abstract]
Costs for additions to oil and natural gas properties	$ 16,281	$ 13,951
Lease operating expenses	9,903	7,309
Interest	18,746	8,566
Production and ad valorem taxes	3,496	4,379
General and administrative expenses	1,981	2,596
Current portion of ARO	1,977	1,977
Derivative settlements	855	364
Other	613	1,029
Accounts Payable and Accrued Liabilities, Current, Total	$ 53,852	$ 40,171