Financial Instruments and Risk Management (Tables)

9 Months Ended

Sep. 30, 2015

Financial Instruments and Risk Management [Abstract]

WTI Open Contracts

	Volumes
At September 30, 2015	(barrels per day)	Swap Prices
October – December 2015	15,000	$ 63.30	per barrel
At September 30, 2014
October – December 2014	22,000	$ 93.26	per barrel

Fair Value of Derivative Instruments Not Designated as Hedging Instruments

	September 30, 2015			December 31, 2014
(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	$	31,999	Accounts receivable	$	23,168
Foreign exchange	Accounts receivable		22	Accounts payable		(25)

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

			Gain (Loss)
		Three Months Ended			Nine Months Ended
(Thousands of dollars)		September 30,			September 30,
Type of Derivative Contract	Statement of Operations Location		2015	2014	2015	2014
Commodity	Sales and other operating revenues	$	39,392	37,305	46,811	(17,150)
Foreign exchange	Interest and other income		33	(838)	47	4,062
		$	39,425	36,467	46,858	(13,088)

Nonrecurring Fair Value Measurements

	September 30, 2015
						Total
					Net Book	Pretax
					Value	(Noncash)
	Fair Value				Prior to	Impairment
		Level 1	Level 2	Level 3	Impairment	Loss
(Thousands of dollars)
Assets:
Impaired proved properties
Gulf of Mexico	$	–	–	216,602	361,402	144,800
Western Canada		–	–	23,526	707,100	683,574
Malaysia		–	–	1,208,900	2,681,500	1,472,600
	$	–	–	1,449,028	3,750,002	2,300,974

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

	September 30, 2015					December 31, 2014
(Thousands of dollars)	Level 1		Level 2	Level 3	Total	Level 1	Level 2	Level 3	Total
Assets:
Foreign currency exchange         derivative contracts	$	–	22	–	22	–	–	–	–
Commodity derivative         contracts		–	31,999	–	31,999	–	23,168	–	23,168
	$	–	32,021	–	32,021	–	23,168	–	23,168
Liabilities:
Nonqualified employee         savings plans	$	12,195	–	–	12,195	14,408	–	–	14,408
Foreign currency exchange         derivative contracts		–	–	–	–	–	25	–	25
	$	12,195	–	–	12,195	14,408	25	–	14,433