Suspended Well Costs (Tables)

12 Months Ended

Dec. 31, 2014

Suspended Well Costs [Abstract]

Capitalized Exploratory Well Costs, Roll Forward [Table Text Block]

The following table reflects the net changes in capitalized exploratory well costs during 2014, 2013, and 2012. The table does not include amounts that were capitalized and either subsequently expensed or reclassified to producing well costs in the same year:

	For the Years Ended December 31,
	2014			2013			2012
	(in thousands)
Beginning balance on January 1,	$	34,527		$	9,100		$	18,600
Additions to capitalized exploratory well costs pending the determination of proved reserves	43,589			34,527			9,100
Reclassifications to wells, facilities, and equipment based on the determination of proved reserves	(33,340		)	(9,100		)	(5,865		)
Capitalized exploratory well costs charged to expense	(1,187		)	—			(12,735		)
Ending balance at December 31,	$	43,589		$	34,527		$	9,100