Fair Value Measurements of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2013

Fair Value Measurements of Financial Instruments

Schedule of commodity derivative contracts recorded at estimated fair value

	Fair Value Measurements at June 30, 2013
	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	(in thousands)
Assets:
Commodity derivative oil swaps	$	—	$	11,428	$	—	$	11,428
Commodity derivative NGL swaps	—		3,461		—		3,461
Commodity derivative gas swaps	—		5,670		—		5,670
Commodity derivative oil collars	—		488		—		488
Commodity derivative gas collars	—		1,539		—		1,539
Commodity derivative differential swaps	—		147		—		147
Total assets	—		22,733		—		22,733
Liabilities:
Commodity derivative oil swaps	$	—	$	17,430	$	—	$	17,430
Commodity derivative NGL swaps	—		—		—		—
Commodity derivative gas swaps	—		—		—		—
Commodity derivative oil collars	—		118		—		118
Commodity derivative gas collars	—		48				48
Commodity derivative differential swaps	—		878		—		878
Total liabilities	$	—	$	18,474	$	—	$	18,474

	Fair Value Measurements at December 31, 2012
	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
	(in thousands)
Assets:
Commodity derivative oil swaps	$	—	$	16,133	$	—	$	16,133
Commodity derivative NGL swaps	—		2,353		—		2,353
Commodity derivative oil collars	—		428		—		428
Commodity derivative gas collars	—		2,026		—		2,026
Commodity derivative differential swaps	—		2,661		—		2,661
Total assets	—		23,601		—		23,601
Liabilities:
Commodity derivative oil swaps	$	—	$	15,091	$	—	$	15,091
Commodity derivative NGL swaps	—		458		—		458
Commodity derivative oil collars	—		287		—		287
Commodity derivative gas collars	—		185		—		185
Commodity derivative differential swaps	—		11,693		—		11,693
Total liabilities	$	—	$	27,714	$	—	$	27,714