Statements of Consolidated Cash Flows (UA) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities:
Net income (loss)	$ 737	$ (1,964)	$ (7,069)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities -
Deferred income tax (benefit)	248	(583)	(1,741)
Depreciation and amortization	2,456	2,485	2,488
Operating and non-operating special charges, non-cash portion	16	32	1,448
Unrealized (gains) losses on investments	(20)	34	194
Amortization of debt discount and debt issuance costs	156	171	94
Other operating activities	218	222	226
Changes in operating assets and liabilities -
(Increase) decrease in receivables	(158)	(448)	135
(Increase) decrease in other assets	(86)	(292)	484
Increase in advance ticket sales	1,200	1,521	14
Increase in frequent flyer deferred revenue	393	307	699
Increase (decrease) in accounts payable	796	985	(1,079)
Increase (decrease) in other liabilities	110	(403)	(26)
Net cash provided by (used in) operating activities	6,066	2,067	(4,133)
Investing Activities:
Capital expenditures, net of flight equipment purchase deposit returns	(4,819)	(2,107)	(1,727)
Purchases of short-term and other investments	(11,232)	(68)	(552)
Proceeds from sale of short-term and other investments	2,084	397	2,319
Proceeds from sale of property and equipment	207	107	6
Other, net	(69)	(1)	4
Net cash provided by (used in) investing activities	(13,829)	(1,672)	50
Financing Activities:
Proceeds from issuance of debt, net of discounts and fees	736	11,096	15,676
Payments of long-term debt, finance leases and other financing liabilities	(4,011)	(5,205)	(4,449)
Proceeds from issuance of parent company stock	0	532	2,103
Other, net	(74)	(27)	(20)
Net cash provided by (used in) financing activities	(3,349)	6,396	12,957
Net increase (decrease) in cash, cash equivalents and restricted cash	(11,112)	6,791	8,874
Cash, cash equivalents and restricted cash at beginning of year	18,533	11,742	2,868
Cash, cash equivalents and restricted cash at end of year	7,421	18,533	11,742
Investing and Financing Activities Not Affecting Cash:
Property and equipment acquired through the issuance of debt, finance leases and other	19	814	1,968
Right-of-use assets acquired through operating leases	137	771	198
Investment interests received in exchange for goods and services	103	295	0
Lease modifications and lease conversions	(84)	123	527
Cash Paid (Refunded) During the Period for:
Interest	1,573	1,424	874
Income taxes	8	0	(29)
United Airlines, Inc.
Operating Activities:
Net income (loss)	739	(1,962)	(7,067)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities -
Deferred income tax (benefit)	248	(583)	(1,741)
Depreciation and amortization	2,456	2,485	2,488
Operating and non-operating special charges, non-cash portion	16	32	1,448
Unrealized (gains) losses on investments	(20)	34	194
Amortization of debt discount and debt issuance costs	156	171	94
Other operating activities	218	222	226
Changes in operating assets and liabilities -
(Increase) decrease in receivables	(158)	(448)	135
Increase in intercompany receivables	(76)	(28)	(14)
(Increase) decrease in other assets	(86)	(293)	484
Increase in advance ticket sales	1,200	1,521	14
Increase in frequent flyer deferred revenue	393	307	699
Increase (decrease) in accounts payable	796	985	(1,079)
Increase (decrease) in other liabilities	110	(403)	(26)
Net cash provided by (used in) operating activities	5,992	2,040	(4,145)
Investing Activities:
Capital expenditures, net of flight equipment purchase deposit returns	(4,819)	(2,107)	(1,727)
Purchases of short-term and other investments	(11,232)	(68)	(552)
Proceeds from sale of short-term and other investments	2,084	397	2,319
Proceeds from sale of property and equipment	207	107	6
Other, net	(69)	(1)	4
Net cash provided by (used in) investing activities	(13,829)	(1,672)	50
Financing Activities:
Proceeds from issuance of debt, net of discounts and fees	736	11,096	15,676
Payments of long-term debt, finance leases and other financing liabilities	(4,011)	(5,205)	(4,449)
Proceeds from issuance of parent company stock	0	532	2,103
Dividend to UAL	0	0	(353)
Other, net	0	0	(2)
Net cash provided by (used in) financing activities	(3,275)	6,423	12,975
Net increase (decrease) in cash, cash equivalents and restricted cash	(11,112)	6,791	8,880
Cash, cash equivalents and restricted cash at beginning of year	18,533	11,742	2,862
Cash, cash equivalents and restricted cash at end of year	7,421	18,533	11,742
Investing and Financing Activities Not Affecting Cash:
Property and equipment acquired through the issuance of debt, finance leases and other	19	814	1,968
Right-of-use assets acquired through operating leases	137	771	198
Investment interests received in exchange for goods and services	103	295	0
Lease modifications and lease conversions	(84)	123	527
Cash Paid (Refunded) During the Period for:
Interest	1,573	1,424	874
Income taxes	$ 8	$ 0	$ (29)