Consolidated Statements Of Cash Flows - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2020
Cash flows provided from (used by) operating activities:
Net Income (loss)	$ 4,541	$ 414	$ 441	$ (402)
Adjustments to reconcile net income to net cash provided from (used by) operating activities:
Depreciation and amortization	506	734	1,182	1,598
Loss on early extinguishment of debt				72
Pension settlement costs			55	159
Stock-based compensation expense	(1)	18	82	3
Non-cash reorganization items, net	(5,467)			93
Amortization of (premium) discount	1	(18)	(28)	5
Lease Impairment			44
Bad debt expense		14	26
Other adjustments				16
Deferred income taxes	(148)	81	164	(91)
Loss on disposal of Northwest Operations				162
Change in accounts receivable	36	45	(7)	73
Change in long-term pension and other post retirement liabilities	(12)	21	(656)	(8)
Change in accounts payable and other liabilities	(156)	94	51	350
Change in prepaid expenses, income taxes, and other assets	46	48	47	(41)
Net cash provided from (used by) operating activities	(654)	1,451	1,401	1,989
Cash flows provided from (used by) investing activities:
Capital expenditures	(500)	(1,205)	(2,738)	(1,181)
Proceeds from sale of Northwest Operations				1,131
Proceeds on sale of assets	9	7	13	27
Purchase of short-term investments			(4,350)
Sale of short-term investments			2,600
Other	1	5	7	4
Net cash used by investing activities	(490)	(1,193)	(4,468)	(19)
Cash flows provided from (used by) financing activities:
Long-term debt principal payments	(1)	(17)	(14)	(4,948)
Proceeds from long-term debt borrowings	225	1,000	1,200	4,950
Repayment of revolving debt				(749)
Financing costs paid	(4)	(13)	(17)	(121)
Finance lease obligation payments	(7)	(13)	(19)	(23)
Proceeds from financing lease transactions			70
Taxes paid on behalf of employees for shares withheld			(8)
Other	(16)	23	(1)	(2)
Net cash provided from (used by) financing activities	197	980	1,211	(893)
Increase (Decrease) in cash, cash equivalents, and restricted cash	(947)	1,238	(1,856)	1,077
Cash, cash equivalents, and restricted cash at the beginning of the period	1,887	940	2,178	810
Cash, cash equivalents, and restricted cash at the end of the period	940	2,178	322	1,887
Cash paid during the period for:
Interest	84	281	512	612
Income tax payments, net	9	28	8	8
Reorganization items, net	1,397			270
Non-cash investing activities:
Increase (Decrease) in capital expenditures due to changes in accounts payable	$ (5)	$ (26)	$ 797	$ (117)
Financial Designation, Predecessor and Successor [Fixed List]	Predecessor	Successor	Successor	Predecessor