Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash Flows from Operating Activities
Net Income (Loss)	$ 1,584,000	$ (900,000)
Items Not Requiring (Providing) Cash
Depreciation, Depletion and Amortization	1,814,000	1,707,000
Impairments	88,000	1,878,000
Stock-Based Compensation Expenses	66,000	80,000
Deferred Income Taxes	(133,000)	(208,000)
Gains (Losses) on Asset Dispositions, Net	45,000	30,000
Other, Net	13,000	0
Dry Hole Costs	24,000	0
Mark-to-Market Commodity Derivative Contracts
Total (Gains) Losses	794,000	(1,079,000)
Net Cash Received from (Payments for) Settlements of Commodity Derivative Contracts	(223,000)	724,000
Other, Net	1,000	0
Changes in Components of Working Capital and Other Assets and Liabilities
Accounts Receivable	(494,000)	1,191,000
Inventories	101,000	85,000
Accounts Payable	183,000	(1,185,000)
Accrued Taxes Payable	80,000	(61,000)
Other Assets	(222,000)	253,000
Other Liabilities	(57,000)	(64,000)
Changes in Components of Working Capital Associated with Investing and Financing Activities	(145,000)	282,000
Net Cash Provided by Operating Activities	3,429,000	2,673,000
Investing Cash Flows
Additions to Oil and Gas Properties	(1,843,000)	(1,990,000)
Additions to Other Property, Plant and Equipment	(97,000)	(147,000)
Proceeds from Sales of Assets	146,000	43,000
Changes in Components of Working Capital Associated with Investing Activities	145,000	(282,000)
Net Cash Used in Investing Activities	(1,649,000)	(2,376,000)
Financing Cash Flows
Long-Term Debt Borrowings	0	1,484,000
Long-Term Debt Repayments	(750,000)	(1,000,000)
Dividends Paid	(458,000)	(384,000)
Treasury Stock Purchased	(12,000)	(5,000)
Proceeds from Stock Options Exercised	9,000	8,000
Debt Issuance Costs	0	(3,000)
Repayment of Finance Lease Liabilities	(18,000)	(8,000)
Net Cash Provided by (Used in) Financing Activities	(1,229,000)	92,000
Effect of Exchange Rate Changes on Cash	0	0
Increase in Cash and Cash Equivalents	551,000	389,000
Cash and Cash Equivalents at Beginning Period	3,329,000	2,028,000
Cash and Cash Equivalents End of Period	$ 3,880,000	$ 2,417,000