Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2012

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

				December 31,
				2012		2011
Derivatives not designated as hedges:
	Oil and gas commodity derivatives:
		Prepaid expenses and other current assets	$	-	$	1,247
	Embedded derivatives related to debt instrument:
		Other liabilities - long-term		(7,402)		(16,067)

Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]

			Year Ended December 31,
			2012		2011		2010
Derivatives not designated as hedges:
	Oil and gas commodity derivatives:
		Realized gains (losses)	$	-	$	-	$	(11,753)
		Unrealized gains (losses)		(3,524)		(3,050)		10,943
				(3,524)		(3,050)		(810)
	Embedded derivatives related to debt and equity instruments:
		Unrealized gains	$	8,665	$	11,428	$	1,348