Acquisitions and Dispositions (Tables)

12 Months Ended

Dec. 31, 2013

Schedule of Revenues and Lease Operating Expenses Attributable to the ST 41 Interests, the ASOP Properties and the Main Pass Interests

	Year Ended December 31,
	2013		2012		2011
	(In thousands)
WD29 Interests:
Revenues	$	3,011	$	-	$	-
Lease operating expenses	$	44	$	-	$	-
Hilcorp Properties:
Revenues	$	208,241	$	37,978	$	-
Lease operating expenses	$	74,404	$	10,982	$	-
ST41 Interests:
Revenues	$	11,189	$	9,262	$	-
Lease operating expenses	$	2,468	$	1,760	$	-
ASOP Properties and Main Pass Interests:
Revenues	$	328,070	$	175,538	$	125,975
Lease operating expenses	$	33,978	$	26,467	$	17,161

Schedule of Consolidated Results of Operations

	Year Ended December 31,
	Pro Forma 2012
(in thousands, except per share data)
Revenue	$	594,510
Net income	$	59,324
Basic earnings per share	$	1.51
Diluted earnings per share	$	1.51

Nexen Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	September 1, 2013
Oil and natural gas properties	$	93,932
Asset retirement obligations		(27,133)
Net assets acquired	$	66,799

Non-Operated Bay Marchand Field Disposition [Member]

Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block]

(In thousands)	January 1, 2013
Oil and natural gas properties	$	35,298
Asset retirement obligations		(3,959)
Other liabilities		(7,311)
Net assets sold	$	24,028

Hilcorp Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	July 1, 2012
Oil and natural gas properties	$	698,660
Asset retirement obligations		(150,959)
Net assets acquired	$	547,701

South Timbalier Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	April 1, 2012
Oil and natural gas properties	$	33,206
Asset retirement obligations		(1,878)
Net assets acquired	$	31,328

ASOP Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	January 1, 2011
Oil and natural gas properties	$	221,751
Asset retirement obligations		(24,858)
Net assets acquired	$	196,893

Main Pass Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	November 1, 2011
Oil and natural gas properties	$	40,826
Asset retirement obligations		(2,991)
Net assets acquired	$	37,835

West Delta 29 Acquisition [Member]

Schedule of Assets Acquired and Liabilities Assumed

(In thousands)	January 1, 2013
Oil and natural gas properties	$	16,696
Asset retirement obligations		(1,398)
Net assets acquired	$	15,298