CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 24, 2016
Statement of Comprehensive Income [Abstract]
Change in foreign currency translation, tax effects	$ (1)	$ (77)	$ 8
Change in fair value of derivatives, tax benefit/(expense)	(149)	(478)	(7)
Adjustment for net (gains)/losses realized and included in net income, tax expense/(benefit)	(104)	475	131
Change in fair value of marketable securities, tax benefit/(expense)	1,156	425	(863)
Adjustment for net (gains)/losses realized and included in net income, tax expense/(benefit)	$ 21	$ 35	$ (31)

Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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