Fair Value Measurements Activity Between Levels of the Fair Value Hierarchy, Assets (Details) - Mortgage- and asset-backed and auction rate securities [Member] - USD ($) $ in Millions |
12 Months Ended | |
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Sep. 27, 2015 |
Sep. 28, 2014 |
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| Activity for Marketable Securities Classified Within Level 3 of the Valuation Hierarchy [Roll Forward] | ||
| Beginning balance of Level 3 | $ 269 | $ 322 |
| Total realized and unrealized gains or losses included in investment income, net | 3 | 11 |
| Total realized and unrealized gains or losses included in other comprehensive income (loss) | (4) | (3) |
| Purchases | 69 | 107 |
| Sales | (46) | (126) |
| Settlements | (64) | (40) |
| Transfers out of Level 3 | (3) | (2) |
| Ending balance of Level 3 | $ 224 | $ 269 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy. No definition available.
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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