CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities:
Net income (loss)	$ 80	$ (1,547)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	96	113
Amortization of debt issuance costs	2	1
Impairments	0	1,479
Deferred income taxes	0	408
(Gain) loss on derivatives, unsettled	169	(246)
Stock-based compensation	0	1
Gain on early extinguishment of debt	0	(28)
Change in assets and liabilities:
Accounts receivable	(33)	53
Accounts payable	33	(86)
Taxes payable	(8)	(6)
Interest payable	(2)	1
Inventories	9	8
Other assets and liabilities	1	9
Net cash provided by operating activities	347	160
Cash Flows From Investing Activities:
Capital investments	(227)	(228)
Proceeds from sale of property and equipment	1	0
Other	(1)	0
Net cash used in investing activities	(227)	(228)
Cash Flows From Financing Activities:
Payments on long-term debt	0	(52)
Payments on revolving credit facility	(923)	(500)
Borrowings under revolving credit facility	790	615
Change in bank drafts outstanding	7	5
Cash paid for tax withholding	(3)	0
Net cash provided by (used in) financing activities	(129)	68
Decrease in cash and cash equivalents	(9)	0
Cash and cash equivalents at beginning of year	13	5
Cash and cash equivalents at end of period	$ 4	$ 5