Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Receivables, allowance for credit losses	$ 12	$ 11
Aircraft fuel, spare, parts and supplies, obsolescence allowance	629	610
Intangibles, accumulated amortization	1,468	1,472
Allowance for credit losses on investments in affiliates and other	$ 17	$ 21
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares, authorized (in shares)	1,000,000,000	1,000,000,000
Common shares, outstanding (in shares)	327,968,615	326,930,321