CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014
OPERATING ACTIVITIES
Net income (loss)		$ (88,275)		$ 284,665
Adjustments to reconcile net income (loss) to net cash provided by continuing operations activities:
Loss from discontinued operations		2,819		27,289
Depreciation, depletion and amortization		884,417		855,242
Amortization of deferred major repair costs		3,404		4,313
Dry hole costs		99,023		127,827
Amortization of undeveloped leases		45,825		37,764
Accretion of asset retirement obligations		23,519		24,392
Deferred and noncurrent income tax charges (benefits)		(194,240)		18,122
Pretax (gains) losses from disposition of assets		(154,123)		4,997
Net decrease in noncash operating working capital		107,171		48,449
Other operating activities, net		(14,329)		22,106
Net cash provided by continuing operations activities		715,211		1,455,166
INVESTING ACTIVITIES
Property additions and dry hole costs		(1,433,615)		(1,840,544)
Proceeds from sales of property, plant and equipment		423,106		3,089
Purchase of investment securities	[1]	(629,763)		(372,861)
Proceeds from maturity of investment securities	[1]	663,343		320,331
Other investing activities, net		(20,568)		(13,007)
Net cash required by investing activities		(997,497)		(1,902,992)
FINANCING ACTIVITIES
Borrowings of debt		823,000		850,000
Repayments of debt		(450,000)
Repayment of capital lease obligation		(4,703)
Purchase of treasury stock		(250,000)		(375,000)
Withholding tax on stock-based incentive awards		(8,976)		(6,784)
Cash dividends paid		(124,581)		(112,126)
Other financing activities, net		(152)		(1,224)
Net cash provided (required) by financing activities		(15,412)		354,866
CASH FLOWS FROM DISCONTINUED OPERATIONS
Operating activities		(85,445)		4,517
Investing activities		5,322		(9,092)
Changes in cash included in current assets held for sale		89,226
Net decrease in cash and cash equivalents of discontinued operations		9,103		(4,575)
Effect of exchange rate changes on cash and cash equivalents		4,555		8,466
Net decrease in cash and cash equivalents		(284,040)		(89,069)
Cash and cash equivalents at January 1		1,193,308	[2]	750,155
Cash and cash equivalents at June 31		$ 909,268		$ 661,086

[1] Investments are Canadian government securities with maturities greater than 90 days at the date of acquisition.

[2] Reclassified to conform to current presentation.