Financial Instruments and Risk Management (Tables)

6 Months Ended

Jun. 30, 2020

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair Value of Derivative Instruments Not Designated as Hedging Instruments

At June 30, 2020 and December 31, 2019, the fair value of derivative instruments not designated as hedging instruments are presented in the following table.

	June 30, 2020			December 31, 2019
(Thousands of dollars)	Asset (Liability) Derivatives			Asset (Liability) Derivatives
Type of Derivative Contract	Balance Sheet Location	Fair Value		Balance Sheet Location	Fair Value
Commodity	Accounts receivable	$	157,809	Accounts payable	$	(33,364)

Recognized Gains and Losses for Derivative Instruments Not Designated as Hedging Instruments

For the three-month and six-month periods ended June 30, 2020 and 2019, the gains and losses recognized in the Consolidated Statements of Operations for derivative instruments not designated as hedging instruments are presented in the following table.

		Gain (Loss)			Gain (Loss)
(Thousands of dollars)	Statement of Operations Location	Three Months Ended June 30,			Six months ended June 30,
Type of Derivative Contract		2020		2019	2020		2019
Commodity	(Loss) gain on crude contracts	$	(75,880)	57,916	$	324,792	57,916

Carrying Value of Assets and Liabilities Recorded at Fair Value on Recurring Basis

The carrying value of assets and liabilities recorded at fair value on a recurring basis at June 30, 2020 and December 31, 2019, are presented in the following table.

	June 30, 2020					December 31, 2019
(Thousands of dollars)	Level 1		Level 2	Level 3	Total	Level 1	Level 2	Level 3	Total
Assets:
Commodity derivative contracts	$	—	157,809	—	157,809	—	—	—	—
	$	—	157,809	—	157,809	—	—	—	—
Liabilities:
Commodity derivative contracts	$	—	—	—	—	—	33,364	—	33,364
Nonqualified employee savings plans	15,703		—	—	15,703	17,035	—	—	17,035
Contingent consideration	—		—	103,258	103,258	—	—	146,787	146,787
	$	15,703	—	103,258	118,961	17,035	33,364	146,787	197,186