Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows provided from (used by) operating activities:
Net Income	$ 3	$ 65
Adjustments to reconcile net income to net cash provided from (used by) operating activities:
Depreciation and amortization	330	284
Stock-based compensation expense	24	15
Lease Impairment		44
Amortization of premium	(7)	(7)
Bad debt expense	7	7
Other adjustments	1
Deferred income taxes		25
Change in accounts receivable	2	54
Change in long-term pension and other postretirement liabilities	(7)	(94)
Change in accounts payable and other liabilities	30	120
Change in prepaid expenses, income taxes, and other assets	6	15
Net cash provided from operating activities	389	528
Cash flows provided from (used by) investing activities:
Capital expenditures	(1,154)	(447)
Purchase of short-term investments	(225)	(900)
Sale of short-term investments	1,075
Other		2
Net cash (used by) investing activities	(304)	(1,345)
Cash flows provided from (used by) financing activities:
Long-term debt principal payments	(4)	(3)
Proceeds from long-term debt borrowings	750
Financing costs paid	(13)
Finance lease obligation payments	(5)	(5)
Taxes paid on behalf of employees for shares withheld	(3)
Other		(4)
Net cash provided from (used by) financing activities	725	(12)
Increase (Decrease) in cash, cash equivalents, and restricted cash	810	(829)
Cash, cash equivalents, and restricted cash at January 1,	322	2,178
Cash, cash equivalents, and restricted cash at March 31,	1,132	1,349
Cash paid during the period for:
Interest	83	36
Income tax payments, net	$ 5	$ 2