CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE OPERATIONS (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net Income	$ 94	$ 37
Related to marketable securities:
Unrealized holding gains (losses) arising during the period	3	(1)
Reclassification of (gains) losses into net income (within Nonoperating Income (Expense), Other - net)	0	(1)
Income tax effect	(1)	1
Marketable securities, net of tax	2	(1)
Related to employee benefit plans:
Reclassification adjustment for amortization of net pension expense (within Wages and benefits)	2	10
Income tax effect	(1)	(4)
Employee benefit plans, net of tax	1	6
Related to interest rate derivative instruments:
Unrealized holding gains (losses) arising during the period	(3)	3
Reclassification of (gains) losses into net income (within Aircraft rent)	2	1
Income tax effect	0	(2)
Interest rate derivative instruments, net of tax	(1)	2
Other comprehensive income	2	7
Comprehensive income	$ 96	$ 44