Deferred Revenue from Volumetric Production Payment (Tables)

12 Months Ended

Dec. 31, 2012

Deferred Revenue Disclosure [Abstract]

Schedule of changes in deferred revenue from the VPP

Changes in deferred revenue from the VPP are as follows:

	December 31, 2012			December 31, 2011
	(In thousands)
Beginning of period	$	—		$	—
Deferred revenue from VPP	45,479			—
Amortization of deferred revenue from VPP	(8,295		)	—
End of period	$	37,184		$	—