CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE OPERATIONS (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net Income	$ 165	$ 104	$ 259	$ 141
Related to marketable securities:
Unrealized holding gains (losses) arising during the period	4	(11)	7	(12)
Reclassification of (gains) losses into Other-net nonoperating income (expense)	(1)	(1)	(1)	(2)
Income tax effect	(1)	4	(2)	5
Marketable securities, net of tax	2	(8)	4	(9)
Related to employee benefit plans:
Reclassification of net pension expense into Wages and benefits	3	11	5	21
Income tax effect	(1)	(3)	(2)	(7)
Employee benefit plans, net of tax	2	8	3	14
Related to interest rate derivative instruments:
Unrealized holding gains (losses) arising during the period	(2)	7	(5)	10
Reclassification of (gains) losses into Aircraft rent	1	2	3	3
Income tax effect	0	(4)	0	(6)
Interest rate derivative instruments, net of tax	(1)	5	(2)	7
Other comprehensive income	3	5	5	12
Comprehensive income	$ 168	$ 109	$ 264	$ 153