Components of Federal and Foreign Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets related to:
Accrued compensation and benefits		$ 961	$ 965
Pensions	[1]	4,462	4,317
Other postretirement benefit obligations		375	386
Contract accounting methods		1,039	989
Foreign company operating losses and credits		70	59
Other		434	198
Valuation allowance	[2]	(76)	(9)
Deferred tax assets, net		7,265	6,905
Deferred tax liabilities related to:
Goodwill and purchased intangibles		474	454
Property, plant and equipment		457	514
Exchanged debt securities and other	[3]	409	485
Deferred tax liabilities		1,340	1,453
Net deferred tax assets	[4]	$ 5,925	$ 5,452

[1] The increase in 2015 was primarily due to the negative investment return on postretirement plan assets (Note 11).

[2] A valuation allowance was provided against certain foreign company deferred tax assets arising from carryforwards of unused tax benefits.

[3] Includes deferred taxes associated with the exchange of debt securities in prior years.

[4] Includes net foreign current deferred tax liabilities, which are included on the Balance Sheets in other current liabilities.