Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2019 and December 31, 2018:

December 31, 2019	Quoted Prices in Active Markets For Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)			Balance at December 31, 2019
(Thousands of dollars)
Assets
Commodity derivative contracts	$	—	$	—	$	272		$	272
Total assets	$	—	$	—	$	272		$	272
Liabilities
Commodity derivative contracts	$	—	$	—	$	(753	)	$	(753	)
Total liabilities	$	—	$	—	$	(753	)	$	(753	)
December 31, 2018	Quoted Prices in Active Markets For Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)			Balance at December 31, 2018
(Thousands of dollars)
Assets
Commodity derivative contracts	$	—	$	—	$	2,394		$	2,394
Total assets	$	—	$	—	$	2,394		$	2,394
Liabilities
Commodity derivative contract	$	—	$	—	$	(98	)	$	(98	)
Total liabilities	$	—	$	—	$	(98	)	$	(98	)

Schedule of Changes in Fair Value of Financial Assets and Liabilities Classified as Level 3

The following table sets forth a reconciliation of changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the year ended December 2019.

(Thousands of  dollars)
Net Assets – December 31, 2018	$	2,296
Total realized and unrealized (gains) losses:
Included in earnings (a)		(4,148	)
Purchases, sales, issuances and settlements		1,371
Net Liabilities — December 31, 2019	$	(481	)

(a) Derivative instruments are reported in revenues as realized gain/loss and on a separately reported line item captioned unrealized gain/loss on derivative instruments.

Effect of Derivative Instruments on Consolidated Balance Sheets

The following table sets forth the effect of derivative instruments on the consolidated balance sheets at December 31, 2019 and 2018:

			Fair Value
(Thousands of dollars)	Balance Sheet Location		December 31,      2019			December 31,      2018
Asset Derivatives:
Derivatives not designated as cash-flow hedging instruments:
Natural gas commodity contracts		Derivative asset short-term	$	146		$	63
Natural gas liquid contracts		Derivative asset short-term		—			138
Crude oil commodity contracts		Derivative asset short-term		126			1,473
Natural gas commodity contracts		Derivative asset long-term and other assets		—			7
Crude oil commodity contracts		Derivative asset short-term and other assets		—			713
Total			$	272		$	2,394
Liability Derivatives:
Derivatives not designated as cash-flow hedging instruments:
Crude oil commodity contracts		Derivative liability short-term	$	(715	)	$	—
Natural gas commodity contracts		Derivative liability short-term		(38	)		(75	)
Natural gas liquid contracts		Derivative liability short-term		—			(13	)
Natural gas commodity contracts		Derivative liability long-term		—			(10	)
Total			$	(753	)	$	(98	)
Total derivative instruments			$	(481	)	$	2,296

Effect of Derivative Instruments on Consolidated Statements of Operations

The following table sets forth the effect of derivative instruments on the consolidated statements of operations for the years ended December 31, 2019 and 2018:

	Location of gain/loss recognized in income	Amount of gain/loss recognized in income
(Thousands of  dollars)		2019			2018
Derivatives not designated as cash-flow hedge instruments:
Natural gas commodity contracts	Unrealized gain (loss) on derivative instruments, net		123			(394	)
Crude oil commodity contracts	Unrealized (loss) gain on derivative instruments, net		(2,776	)		5,600
Natural gas liquids contracts	Unrealized (loss) gain on derivative instruments, net		(124	)		124
Natural gas commodity contracts	Realized gain (loss) on derivative instruments, net		90			(278	)
Crude oil commodity contracts	Realized (loss) on derivative instruments, net		(1,814	)		(3,642	)
Natural gas liquids contracts	Realized gain (loss) on derivative instruments, net		353			(175	)
		$	(4,148	)	$	1,235