Equity Changes in Accumulated Other Comprehensive Loss, Net of Tax (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 29, 2014	Mar. 30, 2013	Mar. 29, 2014	Mar. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	$ (1,144)	$ (3,128)	$ (1,187)	$ (3,266)
Unrealized gains (losses) arising during the period	(7)	103	58	168
Reclassifications of net (gains) losses to net income	(55)	57	(77)	130
AOCI, Ending Balance	(1,206)	(2,968)	(1,206)	(2,968)
Estimated tax rate	37.00%	37.00%
Investments, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	76	20	95	3
Unrealized gains (losses) arising during the period	22	12	40	29
Reclassifications of net (gains) losses to net income	(58)	(7)	(95)	(7)
AOCI, Ending Balance	40	25	40	25
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	114	7	83	(52)
Unrealized gains (losses) arising during the period	(43)	120	(2)	185
Reclassifications of net (gains) losses to net income	(21)	(9)	(31)	(15)
AOCI, Ending Balance	50	118	50	118
Unrecognized Pension and Postretirement Medical Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	(1,246)	(3,161)	(1,271)	(3,234)
Unrealized gains (losses) arising during the period	15	(6)	15	(6)
Reclassifications of net (gains) losses to net income	24	73	49	146
AOCI, Ending Balance	(1,207)	(3,094)	(1,207)	(3,094)
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	(88)	6	(94)	17
Unrealized gains (losses) arising during the period	(1)	(23)	5	(40)
Reclassifications of net (gains) losses to net income	0	0	0	6
AOCI, Ending Balance	$ (89)	$ (17)	$ (89)	$ (17)