CONSOLIDATED STATEMENTS OF COMPREHENSIVE OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Income (Loss)	$ 478	$ (1,324)	$ 769
Related to marketable securities:
Unrealized holding gains (losses) arising during the period	(30)	33	31
Reclassification of (gains) into Other-net non-operating income (expense)	(6)	(14)	(5)
Income tax benefit (expense)	9	(5)	(6)
Marketable securities, net of tax	(27)	14	20
Related to employee benefit plans:
Actuarial gains (losses) related to pension and other post-retirement benefit plans	294	(69)	(71)
Reclassification of net pension expense into Wages and benefits and Other-net non-operating income	33	30	32
Income tax benefit (expense)	(81)	10	10
Employee benefit plans, net of tax	246	(29)	(29)
Related to interest rate derivative instruments:
Unrealized holding gains (losses) arising during the period	17	(21)	(13)
Reclassification of losses into Aircraft rent	0	3	3
Income tax benefit (expense)	(4)	4	2
Interest rate derivative instruments, net of tax	13	(14)	(8)
Other comprehensive income (loss)	232	(29)	(17)
Comprehensive income	$ 710	$ (1,353)	$ 752