Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2018

Derivative Instruments Not Designated as Hedging Instruments [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions

Oil Swaps



Contract Period	NYMEX WTI Volumes	Weighted-Average Contract Price
	(MBbl)	(per Bbl)
First quarter 2019	826	$	60.16
Second quarter 2019	575	$	55.52
Third quarter 2019	1,217	$	61.41
Fourth quarter 2019	1,115	$	59.97
2020	2,491	$	65.68
Total	6,224

Oil Collars



Contract Period	NYMEX WTI Volumes	Weighted-Average Floor Price		Weighted-Average Ceiling Price
	(MBbl)	(per Bbl)		(per Bbl)
First quarter 2019	2,503	$	51.66	$	64.32
Second quarter 2019	2,802	$	52.18	$	64.61
Third quarter 2019	2,364	$	49.07	$	62.67
Fourth quarter 2019	2,386	$	49.08	$	62.65
2020	1,165	$	55.00	$	66.47
Total	11,220

Oil Basis Swaps



Contract Period	WTI Midland-NYMEX WTI Volumes	Weighted-Average Contract Price ⁽¹⁾			NYMEX WTI-ICE Brent Volumes	Weighted-Average Contract Price ⁽²⁾
	(MBbl)	(per Bbl)			(MBbl)	(per Bbl)
First quarter 2019	2,433	$	(4.44	)	—	$	—
Second quarter 2019	2,571	$	(4.49	)	—	$	—
Third quarter 2019	3,291	$	(2.86	)	—	$	—
Fourth quarter 2019	3,338	$	(2.87	)	—	$	—
2020	11,601	$	(1.03	)	2,750	$	(8.03	)
2021	—	$	—		3,650	$	(7.86	)
2022	—	$	—		3,650	$	(7.78	)
Total	23,234				10,050

____________________________________________


⁽¹⁾	Represents the price differential between WTI Midland (Midland, Texas) and NYMEX WTI (Cushing, Oklahoma).


⁽²⁾	Represents the price differential between NYMEX WTI (Cushing, Oklahoma) and ICE Brent (North Sea).

Gas Swaps



Contract Period	IF HSC Volumes	Weighted-Average Contract Price		WAHA Volumes	Weighted-Average Contract Price
	(BBtu)	(per MMBtu)		(BBtu)	(per MMBtu)
First quarter 2019	19,805	$	2.99	—	$	—
Second quarter 2019	10,439	$	2.82	2,803	$	0.69
Third quarter 2019	12,531	$	2.82	2,984	$	1.28
Fourth quarter 2019	14,433	$	2.88	2,962	$	1.75
2020	9,123	$	2.98	2,060	$	2.20
Total ⁽¹⁾	66,331			10,809

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⁽¹⁾	The Company has natural gas swaps in place that settle against Inside FERC Houston Ship Channel (“IF HSC”), Inside FERC West Texas (“IF WAHA”), and Platt’s Gas Daily West Texas (“GD WAHA”). As of December 31, 2018, total volumes for gas swaps are comprised of 86 percent IF HSC, four percent IF Waha, and 10 percent GD Waha.

Gas Collars



Contract Period	IF HSC Volumes	Weighted- Average Floor Price		Weighted- Average Ceiling Price
	(BBtu)	(per MMBtu)		(per MMBtu)
First quarter 2019	—	$	—	$	—
Second quarter 2019	4,358	$	2.50	$	2.83
Third quarter 2019	5,066	$	2.50	$	2.83
Fourth quarter 2019	4,818	$	2.50	$	2.83
Total	14,242

NGL Swaps



	OPIS Ethane Purity Mont Belvieu			OPIS Propane Mont Belvieu Non-TET			OPIS Normal Butane Mont Belvieu Non-TET			OPIS Isobutane Mont Belvieu Non-TET			OPIS Natural Gasoline Mont Belvieu Non-TET
Contract Period	Volumes	Weighted-Average Contract Price		Volumes	Weighted-Average Contract Price		Volumes	Weighted-Average Contract Price		Volumes	Weighted-Average Contract Price		Volumes	Weighted-Average Contract Price
	(MBbl)	(per Bbl)		(MBbl)	(per Bbl)		(MBbl)	(per Bbl)		(MBbl)	(per Bbl)		(MBbl)	(per Bbl)
First quarter 2019	853	$	12.25	540	$	28.72	38	$	35.64	29	$	35.70	48	$	50.93
Second quarter 2019	877	$	12.29	561	$	31.32	38	$	35.64	29	$	35.70	49	$	50.93
Third quarter 2019	907	$	12.34	637	$	31.29	39	$	35.64	30	$	35.70	50	$	50.93
Fourth quarter 2019	896	$	12.36	651	$	31.64	39	$	35.64	29	$	35.70	50	$	50.93
2020	539	$	11.13	—	$	—	—	$	—	—	$	—	—	$	—
Total	4,072			2,389			154			117			197

Schedule of fair value of derivatives in accompanying balance sheets

The following tables detail the fair value of derivatives recorded in the accompanying balance sheets, by category:



	As of December 31, 2018
	Derivative Assets			Derivative Liabilities
	Balance Sheet Classification	Fair Value		Balance Sheet Classification	Fair Value
	(in thousands)
Commodity contracts	Current assets	$	175,130	Current liabilities	$	62,853
Commodity contracts	Noncurrent assets	58,499		Noncurrent liabilities	12,496
Total commodity contracts		$	233,629		$	75,349



	As of December 31, 2017
	Derivative Assets			Derivative Liabilities
	Balance Sheet Classification	Fair Value		Balance Sheet Classification	Fair Value
	(in thousands)
Commodity contracts	Current assets	$	64,266	Current liabilities	$	172,582
Commodity contracts	Noncurrent assets	40,362		Noncurrent liabilities	71,402
Total commodity contracts		$	104,628		$	243,984

Schedule of the potential effects of master netting arrangements

The following table provides a reconciliation between the gross assets and liabilities reflected on the accompanying balance sheets and the potential effects of master netting arrangements on the fair value of the Company’s derivative contracts:



	Derivative Assets						Derivative Liabilities
	As of December 31,						As of December 31,
Offsetting of Derivative Assets and Liabilities	2018			2017			2018			2017
	(in thousands)
Gross amounts presented in the accompanying balance sheets	$	233,629		$	104,628		$	(75,349	)	$	(243,984	)
Amounts not offset in the accompanying balance sheets	(56,041		)	(100,035		)	56,041			100,035
Net amounts	$	177,588		$	4,593		$	(19,308	)	$	(143,949	)

Schedule of gains and losses on derivative instruments in the statement of operations

The following table summarizes the components of the net derivative (gain) loss line item presented in the accompanying statements of operations:



	For the Years Ended December 31,
	2018			2017			2016
	(in thousands)
Derivative settlement (gain) loss:
Oil contracts	$	68,860		$	31,176		$	(243,102	)
Gas contracts	13,029			(87,857		)	(94,936		)
NGL contracts	53,914			35,447			8,560
Total derivative settlement (gain) loss	$	135,803		$	(21,234	)	$	(329,478	)

Net derivative (gain) loss:
Oil contracts	$	(192,002	)	$	71,502		$	85,370
Gas contracts	35,411			(76,315		)	81,060
NGL contracts	(5,241		)	31,227			84,203
Total net derivative (gain) loss	$	(161,832	)	$	26,414		$	250,633