Goodwill and Intangible Assets (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 25, 2016	Mar. 27, 2015	Mar. 25, 2016	Mar. 27, 2015	Sep. 25, 2015
Gross carrying amount and accumulated amortization of intangible assets:
Gross Carrying Amount, Amortizable	$ 2,258		$ 2,258		$ 2,049
Accumulated Amortization	1,538		1,538		1,492
Gross Carrying Amount, Non-Amortizable	305		305		306
Intangible asset amortization expense and estimated aggregate amortization expense ($ in millions):
Intangible asset amortization expense	25	$ 21	48	$ 41
Estimated aggregate amortization expense, remainder of 2014	53		53
Estimated aggregate amortization expense, 2015	95		95
Estimated aggregate amortization expense, 2016	91		91
Estimated aggregate amortization expense, 2017	85		85
Estimated aggregate amortization expense, 2018 and thereafter	396		396
Contracts and related customer relationships
Gross carrying amount and accumulated amortization of intangible assets:
Gross Carrying Amount, Amortizable	1,372		1,372		1,281
Accumulated Amortization	1,017		1,017		991
Intellectual property
Gross carrying amount and accumulated amortization of intangible assets:
Gross Carrying Amount, Amortizable	877		877		760
Accumulated Amortization	516		516		496
Gross Carrying Amount, Non-Amortizable	210		210		210
Franchise rights
Gross carrying amount and accumulated amortization of intangible assets:
Gross Carrying Amount, Non-Amortizable	76		76		76
Other
Gross carrying amount and accumulated amortization of intangible assets:
Gross Carrying Amount, Amortizable	9		9		8
Accumulated Amortization	5		5		5
Gross Carrying Amount, Non-Amortizable	$ 19		$ 19		$ 20