Components of Pretax Net Periodic Benefit Costs (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Qualified defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 286	$ 264	$ 857	$ 791
Interest cost	450	471	1,350	1,413
Expected return on plan assets	(621)	(547)	(1,864)	(1,640)
Recognized net actuarial losses	352	279	1,058	837
Amortization of prior service cost (credit)	20	18	60	55
Total net periodic benefit cost	487	485	1,461	1,456
Retiree medical and life insurance plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	7	7	21	21
Interest cost	29	33	87	99
Expected return on plan assets	(36)	(33)	(109)	(99)
Recognized net actuarial losses	11	8	33	24
Amortization of prior service cost (credit)	(4)	(3)	(13)	(9)
Total net periodic benefit cost	$ 7	$ 12	$ 19	$ 36