Summary of Financial Information for Each Business Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended							9 Months Ended
	Sep. 28, 2014		Dec. 31, 2013		Sep. 29, 2013		Mar. 31, 2013	Sep. 28, 2014		Sep. 29, 2013
Segment Reporting Information [Line Items]
Total net sales	$ 11,114				$ 11,347			$ 33,070		$ 33,825
Operating profit	1,392				1,254			4,250		3,671
Less: CAS pension cost	342	[1]			366	[1]		1,140	[1]	1,099	[1]
FAS/CAS pension income (expense)	84				(121)			255		(362)
Severance charges			(171)				(30)			(30)	[2]
Stock-based compensation	(31)				(38)			(128)		(150)
Other, net	(7)				(42)			(58)		(118)
Total unallocated, net	46				(201)			69		(660)
Total assets	36,933		36,188					36,933
Qualified defined benefit pension plans
Segment Reporting Information [Line Items]
FAS pension expense	(258)	[3]			(487)	[3]		(885)	[3]	(1,461)	[3]
Information Systems & Global Solutions
Segment Reporting Information [Line Items]
Severance charges			(53)
Mission Systems and Training
Segment Reporting Information [Line Items]
Severance charges			(37)
Space Systems
Segment Reporting Information [Line Items]
Severance charges			(81)
Business segments
Segment Reporting Information [Line Items]
Operating profit	1,346				1,455			4,181		4,331
Total assets	26,343		25,812					26,343
Business segments | Aeronautics
Segment Reporting Information [Line Items]
Total net sales	3,544				3,632			10,785		10,225
Operating profit	362				412			1,208		1,198
Total assets	6,082		5,821					6,082
Business segments | Information Systems & Global Solutions
Segment Reporting Information [Line Items]
Total net sales	1,949				2,059			5,800		6,266
Operating profit	175				187			524		570
Total assets	5,909		5,798					5,909
Business segments | Missiles and Fire Control
Segment Reporting Information [Line Items]
Total net sales	1,908				2,003			5,666		6,034
Operating profit	335				356			1,038		1,081
Total assets	4,178		4,159					4,178
Business segments | Mission Systems and Training
Segment Reporting Information [Line Items]
Total net sales	1,679				1,698			5,078		5,298
Operating profit	193				216			628		692
Total assets	6,216		6,512					6,216
Business segments | Space Systems
Segment Reporting Information [Line Items]
Total net sales	2,034				1,955			5,741		6,002
Operating profit	281				284			783		790
Total assets	3,958		3,522					3,958
Intersegment elimination
Segment Reporting Information [Line Items]
Total intersegment sales	617				559			1,851		1,673
Intersegment elimination | Aeronautics
Segment Reporting Information [Line Items]
Total intersegment sales	21				53			78		152
Intersegment elimination | Information Systems & Global Solutions
Segment Reporting Information [Line Items]
Total intersegment sales	159				160			507		523
Intersegment elimination | Missiles and Fire Control
Segment Reporting Information [Line Items]
Total intersegment sales	81				72			244		196
Intersegment elimination | Mission Systems and Training
Segment Reporting Information [Line Items]
Total intersegment sales	331				249			944		728
Intersegment elimination | Space Systems
Segment Reporting Information [Line Items]
Total intersegment sales	25				25			78		74
Corporate
Segment Reporting Information [Line Items]
Total assets	$ 10,590	[4]	$ 10,376	[4]				$ 10,590	[4]

[1] CAS pension cost for the quarter ended September 28, 2014 was less than in the quarter ended September 29, 2013 due to the effect of using a higher interest rate required by the Highway and Transportation Funding Act of 2014 (HATFA), which was enacted on August 8, 2014. The higher CAS pension cost during the nine months ended September 28, 2014 reflects the impact of phasing in CAS Harmonization, partially offset by the effect of higher interest rates required by the HATFA. The effect of adopting the HATFA reduced our CAS pension cost by $55 million (including $35 million related to the first six months of 2014) in the quarter and nine months ended September 28, 2014. See "Critical Accounting Policies - Postretirement Benefit Plans" for a discussion of HATFA and CAS Harmonization and the impact on our CAS pension cost.

[2] Severance charges during the nine months ended September 29, 2013 consisted of amounts, net of state tax benefits, associated with the elimination of certain positions at our IS&GS business segment (Note 8, under the caption "Restructuring Charges"). Severance charges for initiatives that are not significant are included in business segment operating profit.

[3] FAS pension expense for the quarter and nine months ended September 28, 2014 was less than in the quarter and nine months ended September 29, 2013 due to higher discount rates used to calculate our qualified defined benefit obligations and net periodic benefit cost. Additionally, the June 2014 plan amendments to certain of our defined benefit pension plans to freeze future retirement benefits reduced FAS pension expense beginning in the quarter ended September 28, 2014 (Note 5, under the caption "Plan Amendments and Re-measurements").

[4] 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.