Reconciliation Of Benefit Obligations, Plan Assets, And Unfunded Status (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at end of year	$ 32,888		$ 29,041
Qualified Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations at beginning of year	40,616		35,773
Service cost	1,055	[1]	974	[1]	903	[1]
Interest cost	1,884	[1]	1,918	[1]	1,876	[1]
Benefits paid	(2,094)	[2]	(1,685)	[2]
Actuarial losses (gains)	4,442		3,632
Plan amendments	114		4
Benefit obligations at end of year	46,017		40,616		35,773
Fair value of plan assets at beginning of year	27,292		25,345
Actual return on plan assets	2,089		1,347
Company contributions	3,637		2,285
Fair value of plan assets at end of year	30,924		27,292		25,345
Unfunded status of the plans	(15,093)		(13,324)
Retiree Medical And Life Insurance Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations at beginning of year	3,023		3,046
Service cost	28		32		36
Interest cost	131		162		166
Benefits paid	(364)	[2]	(363)	[2]
Actuarial losses (gains)	169		(28)
Plan amendments	(6)		11
Medicare Part D subsidy	48		2
Participants' contributions	155		161
Benefit obligations at end of year	3,184		3,023		3,046
Fair value of plan assets at beginning of year	1,749		1,833
Actual return on plan assets	141		116
Company contributions	235
Fair value of plan assets at end of year	1,964		1,749		1,833
Unfunded status of the plans	$ (1,220)		$ (1,274)

[1] Total net periodic benefit cost associated with our qualified defined benefit plans represents pension expense calculated in accordance with GAAP (FAS expense). We are required to calculate pension expense in accordance with both GAAP and CAS rules, each of which results in a different calculated amount of pension expense. The CAS expense is recovered through the pricing of our products and services on U.S. Government contracts and, therefore, is recognized in net sales and cost of sales for products and services. We include the difference between FAS expense and CAS expense, referred to as the non-cash FAS/CAS pension adjustment ($(830) million in 2012, $(922) million in 2011, and $(454) million in 2010), as a component of other unallocated costs on our Statements of Earnings. The non-cash FAS/CAS pension adjustment effectively adjusts the amount of CAS pension expense in the business segment operating profit so that pension expense recorded on our Statements of Earnings is equal to FAS expense.

[2] Benefits paid in 2012 for qualified defined benefit pension plans include $310 million in the form of lump-sum settlement payments to former employees who had not commenced receiving their vested benefit payments. The corresponding benefit obligation that was released was $375 million. The settlement payments had no impact on our 2012 FAS pension expense and CAS pension cost.