Derivative Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Summary of Open Commodity Derivative Contracts

Type	Commodity Reference Price	Remaining Contract Period	Volume - MMBTU/Day		Average Price /MMBTU			Fair Value - March 31, 2018
Natural Gas								Asset (Liability)
Fixed price swaps
	NYMEX-Henry Hub	Apr - Oct 2018		770,000	$	2.88		$	13,951
	NYMEX-Henry Hub	Nov - Dec 2018		290,000	$	2.87			(1,485	)
	NYMEX-Henry Hub	Nov 2018 - Mar 2019		350,000	$	2.95			(2,734	)
	NYMEX-Henry Hub	Jan - Mar 2019		250,000	$	3.02			(441	)
	NYMEX-Henry Hub	Jan - Dec 2019		100,000	$	2.79			(217	)
	NYMEX-Henry Hub	Nov 2018 - Dec 2019		70,000	$	2.80			(377	)
Type	Commodity Reference Price	Remaining Contract Period	Volume - MMBTU/Day		Average Differential /MMBTU			Fair Value - March 31, 2018
Natural Gas								Asset (Liability)
Basis swap contracts (1)
	NW Rockies Basis Swap	Apr - Oct 2018		140,000	$	(0.62	)	$	4,640
	NW Rockies Basis Swap	Apr - Dec 2018		50,000	$	(0.65	)		1,506
	NW Rockies Basis Swap	Apr 2018- Dec 2019		70,000	$	(0.78	)		(112	)
	NW Rockies Basis Swap	Jan-Dec 2019		50,000	$	(0.76	)		488
Type	Commodity Reference Price	Remaining Contract Period	Volume - Bbls/Day		Average Price /Bbls			Fair Value - March 31, 2018
Crude Oil								Asset (Liability)
Fixed price swaps
	NYMEX-WTI	Apr - Dec 2018		5,000	$	60.25		$	(4,075	)
	NYMEX-WTI	Jan - Mar 2019		3,000	$	58.76			(422	)
	NYMEX-WTI	Jan - June 2019		1,000	$	57.70			(365	)
	NYMEX-WTI	Jan - Dec 2019		1,000	$	56.75			(701	)
	NYMEX-WTI	Apr - June 2019		2,000	$	58.21			(173	)
	NYMEX-WTI	July - Sep 2019		1,000	$	57.75			(34	)
	NYMEX-WTI	Apr 2018-Mar 2020		1,000	$	60.05			(88	)

⁽¹⁾ Represents swap contracts that fix the basis differentials for gas sold at or near Opal, Wyoming and the value of natural gas established on the last trading day of the month by the NYMEX for natural gas swaps for the respective period.

Subsequent to March 31, 2018 and through April 25, 2018, the Company has entered into the following open commodity derivative contracts to manage commodity price risk.

Type	Commodity Reference Price	Remaining Contract Period	Volume - MMBTU/Day		Average Price /MMBTU
Natural Gas
Fixed price swaps
	NYMEX-Henry Hub	Nov 2018-Mar 2019		50,000	$	2.98
	NYMEX-Henry Hub	Apr 2019-Mar 2020		50,000	$	2.77
Type	Commodity Reference Price	Remaining Contract Period	Volume - MMBTU/Day		Average Differential /MMBTU
Natural Gas
Basis swap contracts (1)
	NW Rockies Basis Swap	May-Oct 2018		70,000	$	(0.77	)
	NW Rockies Basis Swap	May-Dec 2018		70,000	$	(0.78	)
	NW Rockies Basis Swap	Dec 2018-Mar 2019		90,000	$	(0.69	)
	NW Rockies Basis Swap	Jan - Mar 2019		40,000	$	(0.71	)
Type	Commodity Reference Price	Remaining Contract Period	Volume - Bbls/Day		Average Price /Bbls
Crude Oil
Fixed price swaps
	NYMEX-WTI	May-June 2018		500	$	64.88
	NYMEX-WTI	June 2018		400	$	66.40
	NYMEX-WTI	July-Sep 2018		500	$	65.23
	NYMEX-WTI	Oct-Dec 2018		500	$	63.25
	NYMEX-WTI	July-Sep 2019		1,000	$	59.80

⁽¹⁾ Represents swap contracts that fix the basis differentials for gas sold at or near Opal, Wyoming and the value of natural gas established on the last trading day of the month by the NYMEX for natural gas swaps for the respective period.

Summary of Pre-tax Realized and Unrealized Gain (Loss) Recognized Related to Derivative Instruments

	For the Quarter Ended
	Ended March 31,
Commodity Derivatives:	2018			2017
Realized gain on commodity derivatives - natural gas (1)	$	1,446		$	—
Realized loss on commodity derivatives - oil (1)		(370	)		—
Unrealized loss on commodity derivatives (1)		(7,606	)		(13,218	)
Total loss on commodity derivatives	$	(6,530	)	$	(13,218	)

⁽¹⁾ Included in Loss on commodity derivatives in the Consolidated Statements of Operations.