Details about Accumulated Other Comprehensive Income Components (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Salaries And Related Costs
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of unrecognized (gains) losses and prior service cost (credit)	[1],[2]	$ 8	$ (18)	$ 18	$ (34)
Miscellaneous, Net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Available for sale securities-reclassifications of gains into earnings	[1]		(6)	(1)	(6)
Fuel Oil Contract | Cash Flow Hedging | Aircraft Fuel
Accumulated Other Comprehensive Income (Loss) [Line Items]
Fuel contracts-reclassifications of (gains) losses into earnings	[1]	$ 118	$ 1	$ 279	$ 4

[1] Income tax expense for these items was offset by the Company's valuation allowance.

[2] This AOCI component is included in the computation of net periodic pension and other postretirement costs (see Note 5 of this report for additional information).