Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Cash flows provided from (used by) operating activities:
Net loss	$ (187)	$ (122)
Adjustments to reconcile net income to net cash provided from (used by) operating activities:
Depreciation and amortization	902	786
Pension / OPEB special termination benefit enhancements		10
Stock-based compensation expense	28	37
Amortization of premium	(11)	(10)
Bad debt expense	21	20
Other adjustments	10	7
Deferred income taxes	(30)	(10)
Change in accounts receivable	(72)	(8)
Change in long-term pension and other postretirement liabilities	(102)	(118)
Change in accounts payable and other liabilities	446	76
Change in prepaid expenses, income taxes, and other assets	(9)	41
Net cash provided from operating activities	996	709
Cash flows provided from (used by) investing activities:
Capital expenditures	(1,602)	(1,292)
Sale of short-term investments		1,075
Proceeds on sale of assets	3	4
Other	2	6
Net cash used by investing activities	(1,597)	(207)
Cash flows provided from (used by) financing activities:
Long-term debt principal payments	(3)	(7)
Net proceeds from long-term debt borrowings	330
Payments of vendor financing	(16)	(415)
Financing costs paid	(17)
Finance lease obligation payments	(21)	(15)
Taxes paid on behalf of employees for shares withheld	(11)	(49)
Other	(8)	(9)
Net cash provided from (used by) financing activities	254	(495)
Increase (Decrease) in cash, cash equivalents, and restricted cash	(347)	7
Cash, cash equivalents, and restricted cash at January 1,	911	1,239
Cash, cash equivalents, and restricted cash at June 30,	564	1,246
Supplemental cash flow information: Cash paid during the period for:
Interest	406	412
Income tax payments (refund), net	$ 2	$ (9)