Contracts in Process - General and Administrative, Independent Research and Development and Bids and Proposal Costs (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 24, 2016	Jun. 26, 2015	Jun. 24, 2016	Jun. 26, 2015
Inventory Disclosure [Abstract]
Amounts included in inventoried contract costs at beginning of the period	$ 157	$ 128	$ 137	$ 117
Contract costs incurred:
IRAD and B&P	72	72	137	135
Other G&A	216	199	410	394
Total	288	271	547	529
Amounts charged to cost of sales	(282)	(273)	(521)	(520)
Amounts included in inventoried contract costs at end of the period	$ 163	$ 126	$ 163	$ 126