Employee Stock and Benefit Plans (Stock Option Transactions) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Sep. 30, 2018	Oct. 01, 2017	Oct. 02, 2016
Shares Subject to Options
Outstanding, September 27, 2015, Shares Subject to Options	31.4
Granted, Shares Subject to Options	3.9
Exercised, Shares Subject to Options	(6.3)
Expired/forfeited, Shares Subject to Options	(1.7)
Outstanding, October 2, 2016, Shares Subject to Options	27.3	31.4
Exercisable, October 2, 2016, Shares Subject to Options	19.8
Vested and expected to vest, October 2, 2016, Shares Subject to Options	26.3
Weighted Average Exercise Price per Share
Outstanding, September 27, 2015, Weighted Average Exercise Price per Share Beginning Balance	$ 36.51
Granted, Weighted Average Exercise Price per Share	56.56	$ 56.12	$ 60.20
Exercised, Weighted Average Exercise Price per Share	19.46
Expired/forfeited, Weighted Average Exercise Price per Share	55.24
Outstanding, October 2, 2016, Weighted Average Exercise Price per Share Ending Balance	42.13	$ 36.51
Exercisable at October 2, 2016, Weighted Average Exercise Price per Share	36.95
Vested and expected to vest, October 2, 2016, Weighted Average Exercise Price per Share	$ 41.59
Additional Disclosures
Outstanding, Weighted Average Remaining Contractual Life (Years)	5 years 2 months 12 days	5 years 9 months 18 days
Exercisable, October 2, 2016, Weighted Average Remaining Contractual Life (Years)	4 years 1 month 6 days
Vested and expected to vest, October 2, 2016, Weighted Average Remaining Contractual Life (Years)	5 years 1 month 6 days
Aggregate Intrinsic Value
Outstanding, Aggregate Intrinsic Value	$ 418	$ 589
Exercisable, October 2, 2016, Aggregate Intrinsic Value	405
Vested and expected to vest, October 2, 2016, Aggregate Intrinsic Value	$ 417

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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