Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 1,342	$ 2,056
Reconciliation of net income to net cash provided by operating activities:
Depreciation	867	854
Deferred income taxes	78	225
Gains and losses on properties	(14)	(4)
Loss on asset disposal	385	0
Impairment of investment	99	0
Changes in assets and liabilities affecting operations:
Accounts receivable	36	34
Materials and supplies	(3)	(59)
Other current assets	55	40
Current liabilities other than debt	104	(72)
Other – net	(182)	(77)
Net cash provided by operating activities	2,767	2,997
Cash flows from investing activities:
Property additions	(1,053)	(1,494)
Property sales and other transactions	291	282
Investment purchases	(6)	(12)
Investment sales and other transactions	(50)	(99)
Net cash used in investing activities	(818)	(1,323)
Cash flows from financing activities:
Dividends	(722)	(705)
Common stock transactions	53	21
Purchase and retirement of common stock	(960)	(1,550)
Proceeds from borrowings – net of issuance costs	784	1,404
Debt repayments	(325)	(750)
Net cash used in financing activities	(1,170)	(1,580)
Net increase in cash, cash equivalents, and restricted cash	779	94
Cash, cash equivalents, and restricted cash:
At beginning of year	580	446
At end of period	1,359	540
Supplemental disclosures of cash flow information:
Interest (net of amounts capitalized)	395	392
Income taxes (net of refunds)	$ 118	$ 404