Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating Activities
Net income	$ 2,511	$ 3,035
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,300	1,247
Deferred income taxes	111	(62)
Other, net	(81)	(115)
Changes in current assets and liabilities:
Accounts receivable, net	72	(239)
Materials and supplies	17	(198)
Other current assets	(21)	5
Accounts payable and other current liabilities	(812)	88
Net cash provided by operating activities	3,097	3,761
Investing Activities
Capital expenditures excluding equipment	(1,605)	(1,402)
Acquisition of equipment	(72)	(39)
Purchases of investments and investments in time deposits	(21)	0
Other, net	(176)	(149)
Net cash used in investing activities	(1,874)	(1,590)
Financing Activities
Proceeds from issuance of long-term debt	1,600	1,000
Payments on long-term debt and finance leases	(737)	(831)
Cash distributions	(1,100)	(2,100)
Other, net	(13)	(14)
Net cash used in financing activities	(250)	(1,945)
Increase (decrease) in cash and cash equivalents	973	226
Cash and cash equivalents:
Beginning of period	1,938	1,758
End of period	2,911	1,984
Supplemental Cash Flow Information
Interest paid, net of amounts capitalized	517	516
Capital investments accrued but not yet paid	362	205
Income taxes paid, net of refunds	825	934
Non-cash asset financing	$ 0	$ 3