Composition of Certain Financial Statement Captions (Details) (USD $)	12 Months Ended
	Sep. 25, 2011	Sep. 26, 2010	Sep. 27, 2009
Accounts Receivable [Abstract]
Allowance for doubtful accounts	$ 2,000,000	$ 3,000,000
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	704,000,000	437,000,000	428,000,000
Gross book values of property under capital leases	175,000,000	227,000,000
Capital lease additions	1,000,000	40,000,000	50,000,000
Buildings and improvements and leasehold improvements leased to third parties or held for lease to third parties, net book value	19,000,000	38,000,000
Buildings and improvements and leasehold improvements leased to third parties or held for lease to third parties, accumulated depreciation and amortization	8,000,000	8,000,000
Future minimum rental income - fiscal 2012	5,000,000
Future minimum rental income - fiscal 2013	3,000,000
Future minimum rental income - fiscal 2014	2,000,000
Future minimum rental income - fiscal 2015	1,000,000
Future minimum rental income - after fiscal 2015	0
Goodwill and Other Intangible Assets [Abstract]
Goodwill impairment	114,000,000	0	0
Goodwill balance for Firethorn reporting unit	40,000,000
Carrying value of spectrum held for sale	746,000,000	0
Wireless licenses not subject to amortization	16,000,000
Amortization expense related to intangible assets	357,000,000	227,000,000	207,000,000
Expected Amortization Expense for Intangible Assets [Abstract]
Expected amortization expense - fiscal 2012	457,000,000
Expected amortization expense - fiscal 2013	438,000,000
Expected amortization expense - fiscal 2014	426,000,000
Expected amortization expense - fiscal 2015	385,000,000
Expected amortization expense - fiscal 2016	277,000,000
Expected amortization expense - after fiscal 2016	$ 1,100,000,000