Fair Value Measurements (Details) (Fair value, Measurements, Recurring [Member], USD $) In Millions, unless otherwise specified	Sep. 28, 2014	Sep. 29, 2013
Level 1 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Total	$ 50	$ 73
Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Total	688	1,156
Total [Member]
Assets, Fair Value Disclosure [Abstract]
Total	738	1,229
Money Market Funds [Member] | Level 1 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	46	73
Money Market Funds [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	46	73
US Treasury Bill Securities [Member] | Level 1 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	4
US Treasury Bill Securities [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	4
Commercial Paper [Member] | Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	15	104
Marketable Securities - Available-for-sale	33
Commercial Paper [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents	15	104
Marketable Securities - Available-for-sale	33
Municipal Notes Bonds [Member] | Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents		17
Marketable Securities - Available-for-sale	530	1,010
Municipal Notes Bonds [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Equivalents		17
Marketable Securities - Available-for-sale	530	1,010
Asset-backed Securities [Member] | Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale	13
Asset-backed Securities [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale	13
Corporate Debt Securities [Member] | Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale	97	5
Corporate Debt Securities [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale	97	5
Variable Rate Demand Obligation [Member] | Level 2 Inputs [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale		20
Variable Rate Demand Obligation [Member] | Total [Member]
Assets, Fair Value Disclosure [Abstract]
Marketable Securities - Available-for-sale		$ 20