Changes in Balance of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015		Sep. 28, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance				$ (11,870)		$ (9,601)
Net actuarial losses	[1]					(3,778)
Prior service credits	[1]					3,043
Other						(48)
Total other comprehensive (loss) income before reclassifications				(88)		(783)
Amounts reclassified from AOCL
Recognition of net actuarial losses	[2]			831		556
Amortization of net prior service cost (credits)	[2]			(194)		(36)
Other				0
Total reclassified from AOCL				637		520
Other comprehensive income (loss), net of tax		$ 135	$ 120	549		(263)
Ending balance		(11,321)	(9,864)	(11,321)		(9,864)
Postretirement Benefit Plan Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance				(11,813)		(9,649)
Net actuarial losses	[1]					(3,778)
Prior service credits	[1]					3,043
Total other comprehensive (loss) income before reclassifications						(735)
Amounts reclassified from AOCL
Recognition of net actuarial losses		277	250	831	[2]	556	[2]
Amortization of net prior service cost (credits)		(65)	(64)	(194)	[2]	(36)	[2]
Other				0
Total reclassified from AOCL		212	186	637		520
Other comprehensive income (loss), net of tax				637		(215)
Ending balance		(11,176)	$ (9,864)	(11,176)		(9,864)
Other, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance				(57)		48
Other						(48)
Total other comprehensive (loss) income before reclassifications				(88)		(48)
Amounts reclassified from AOCL
Other				0
Other comprehensive income (loss), net of tax				(88)		$ (48)
Ending balance		$ (145)		$ (145)

[1] Changes in AOCL before reclassifications in 2014 related to our postretirement benefit plans include net actuarial losses from the re-measurement of substantially all our defined benefit pension plans in June 2014 and prior service credits from the June 2014 plan amendments to freeze future retirement benefits in certain of our qualified and non-qualified defined benefit pension plans for non-union employees.

[2] Reclassifications from AOCL related to our postretirement benefit plans were recorded as a component of net periodic benefit cost for each period presented (Note 6). These amounts include $212 million and $186 million for the quarters ended September 27, 2015 and September 28, 2014, which are comprised of the recognition of net actuarial losses of $277 million and $250 million for the quarters ended September 27, 2015 and September 28, 2014 and the amortization of net prior service (credits) costs of $(65) million and $(64) million for the quarters ended September 27, 2015 and September 28, 2014.