CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash Flows From Operating Activities:
Net income	$ 732	$ 259	[1]
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	233	285
Amortization of debt issuance costs	2	4
Deferred income taxes	(411)	0
(Gain) loss on derivatives, unsettled	(96)	54
Stock-based compensation	4	9
Loss on early extinguishment of debt	0	8
Loss on sale of assets, net	3	0
Other	10	1
Change in assets and liabilities:
Accounts receivable	221	12
Accounts payable	(129)	53
Taxes payable	(6)	(4)
Interest payable	1	(1)
Inventories	4	(7)
Other assets and liabilities	(25)	(9)
Net cash provided by operating activities	543	664
Cash Flows From Investing Activities:
Capital investments	(586)	(684)
Proceeds from sale of property and equipment	26	6
Other	0	3
Net cash used in investing activities	(560)	(675)
Cash Flows From Financing Activities:
Payments on long-term debt	0	(1,191)
Payments on revolving credit facility	0	(645)
Borrowings under revolving credit facility	0	1,005
Change in bank drafts outstanding	(7)	0
Debt issuance costs	0	(9)
Purchase of treasury stock	(21)	0
Preferred stock dividend	0	(27)
Cash paid for tax withholding	(1)	(1)
Net cash used in financing activities	(29)	(868)
Decrease in cash and cash equivalents	(46)	(879)
Cash and cash equivalents at beginning of year	201	916
Cash and cash equivalents at end of period	$ 155	$ 37

[1] In 2018, deferred tax activity incurred in other comprehensive income was offset by a valuation allowance.