Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2011

Summary of Property and Equipment

The following table summarizes our property and equipment as of the dates presented:

	As of December 31,
	2011			2010
Oil and gas properties:
Proved	$	2,239,186		$	2,021,729
Unproved		120,288			171,303
Total oil and gas properties		2,359,474			2,193,032
Other property and equipment		143,285			133,754
Total property and equipment		2,502,759			2,326,786
Accumulated depreciation, depletion and amortization		(725,184	)		(621,202	)
	$	1,777,575		$	1,705,584

Changes in Capitalized Exploratory Drilling Costs

The following table describes the changes in capitalized exploratory drilling costs that are pending the determination of proved reserves for the periods presented:

	2011						2010				2009
	Number						Number				Number
	of Wells			Cost			of Wells		Cost		of Wells			Cost
Balance at beginning of year		1		$	6,180			-	$	-		1		$	2,482
Additions pending determination of proved reserves		-			-			1		6,180		-			-
Reclassification to wells, equipment and facilities based on the determination of proved reserves		-			-			-		-		(1	)		(2,482	)
Charged to exploration expense		(1	)		(6,180	)		-		-		-			-
Balance at end of year		-		$	-			1	$	6,180		-		$	-