CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE OPERATIONS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income	$ 605	$ 508	$ 316
Related to marketable securities:
Unrealized holding gains (losses) arising during the period	2	(9)	9
Reclassification of (gains) losses into Other-net nonoperating income (expense)	(2)	(2)	(7)
Income tax benefit (expense)	0	4	(1)
Marketable securities, net of tax	0	(7)	1
Related to employee benefit plans:
Actuarial gains/(losses) related to pension and other post retirement benefit plans	(210)	358	(107)
Reclassification of net pension expense into Wages and benefits	9	42	39
Income tax benefit (expense)	76	(150)	25
Employee benefit plans, net of tax	(125)	250	(43)
Related to interest rate derivative instruments:
Unrealized holding gains (losses) arising during the period	(8)	10	(10)
Reclassification of (gains) losses into Aircraft rent	6	6	6
Income tax benefit (expense)	0	(6)	0
Interest rate derivative instruments, net of tax	(2)	10	(4)
Other comprehensive loss	(127)	253	(46)
Comprehensive income	$ 478	$ 761	$ 270