Summary of Financial Information for Each Business Segment (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total net sales		$ 11,461	$ 11,114	$ 33,215	$ 33,070
Less: CAS pension cost		403	342	1,210	1,140
FAS/CAS pension adjustment		119	84	358	255
Stock-based compensation		(29)	(31)	(118)	(128)
Severance charges	[1]	(35)		(35)
Other, net		(70)	(7)	(125)	(58)
Total unallocated items		(15)	46	80	69
Operating profit		1,354	1,392	4,155	4,250
Total assets		39,617		39,617		$ 37,073
Qualified defined benefit pension plans
Segment Reporting Information [Line Items]
FAS pension expense		(284)	(258)	(852)	(885)
Business segments
Segment Reporting Information [Line Items]
Operating profit		1,369	1,346	4,075	4,181
Total assets		27,615		27,615		26,490
Business segments | Aeronautics
Segment Reporting Information [Line Items]
Total net sales		3,921	3,544	11,186	10,785
Operating profit		418	362	1,233	1,208
Total assets		6,908		6,908		6,021
Business segments | Information Systems & Global Solutions
Segment Reporting Information [Line Items]
Total net sales		1,870	1,949	5,637	5,800
Operating profit		163	175	459	524
Total assets		5,884		5,884		6,228
Business segments | Missiles and Fire Control
Segment Reporting Information [Line Items]
Total net sales		1,938	1,908	5,218	5,666
Operating profit		336	335	931	1,038
Total assets		4,424		4,424		4,050
Business segments | Mission Systems and Training
Segment Reporting Information [Line Items]
Total net sales		1,802	1,679	5,261	5,078
Operating profit		220	193	673	628
Total assets		6,217		6,217		6,277
Business segments | Space Systems
Segment Reporting Information [Line Items]
Total net sales		1,930	2,034	5,913	5,741
Operating profit		232	281	779	783
Total assets		4,182		4,182		3,914
Intersegment elimination
Segment Reporting Information [Line Items]
Total intersegment sales		649	617	1,952	1,851
Intersegment elimination | Aeronautics
Segment Reporting Information [Line Items]
Total intersegment sales		21	21	65	78
Intersegment elimination | Information Systems & Global Solutions
Segment Reporting Information [Line Items]
Total intersegment sales		148	159	513	507
Intersegment elimination | Missiles and Fire Control
Segment Reporting Information [Line Items]
Total intersegment sales		102	81	291	244
Intersegment elimination | Mission Systems and Training
Segment Reporting Information [Line Items]
Total intersegment sales		342	331	987	944
Intersegment elimination | Space Systems
Segment Reporting Information [Line Items]
Total intersegment sales		36	$ 25	96	$ 78
Corporate
Segment Reporting Information [Line Items]
Total assets	[2]	$ 12,002		$ 12,002		$ 10,583

[1] Severance charges for 2015 consist of amounts associated with the planned elimination of certain positions at our IS&GS business segment (Note 9, under the caption "Restructuring Charges"). Severance charges for initiatives that are not significant are included in business segment operating profit.

[2] Corporate assets primarily include cash and cash equivalents, deferred income taxes, environmental receivables and investments held in a separate trust to fund certain of our non-qualified deferred compensation plans.