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Business Combination, Share Consolidation Ratio

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Fair Value of Acquiree Equity Awards not Earned as of Merger Date

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Number of share-based compensation plans.

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Share Based Compensation, Award Modificaton, Conversion Ratio

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Stock Based Compensation Activity [Line Items]

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-based Compensation (Details) $ / shares in Units, shares in Millions, $ in Millions			12 Months Ended
	Oct. 31, 2016	Sep. 02, 2016 USD ($)	Sep. 30, 2018 USD ($) Plan $ / shares shares	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2016 USD ($) $ / shares	Jan. 23, 2013 shares
Stock Based Compensation Activity [Line Items]
Shares authorized for issuance under 2012 Plan (in shares) \| shares						76
Shares available for issuance under the 2012 Plan (in shares) \| shares			45
Tyco share consolidation ratio		0.955			0.955
Business Combination, Consideration Transferred, Fair Value of Acquiree Equity Awards		$ 224
Fair Value of Acquiree Equity Awards not Earned as of Merger Date		$ 101
Number of share-based compensation plans \| Plan			4
Compensation cost charged against income from share-based compensation plans			$ 98	$ 134	$ 160
Total income tax benefit recognized for share-based compensation arrangements			25	53	56
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options			3	4	11
Proceeds from the exercise of stock options			$ 66	$ 157	$ 70
Employee Stock Option
Stock Based Compensation Activity [Line Items]
Expiration period for stock options			10 years
Weighted-average grant-date fair value of options granted \| $ / shares			$ 7.04	$ 7.81	$ 13.14
Total intrinsic value of options exercised			$ 38	$ 81	$ 39
Proceeds from the exercise of stock options			66	157	70
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted			$ 13
Weighted average period over which unrecognized compensation cost is expected to be recognized			1 year 219 days
Stock Appreciation Rights (SARs)
Stock Based Compensation Activity [Line Items]
Share Based Compensation, Award Modificaton, Conversion Ratio	1.085317
Payments towards exercise of SARs granted			$ 3	$ 4	8
Restricted (Nonvested) Stock
Stock Based Compensation Activity [Line Items]
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted			$ 80
Weighted average period over which unrecognized compensation cost is expected to be recognized			1 year 292 days
Minimum \| Employee Stock Option
Stock Based Compensation Activity [Line Items]
Vesting period			2 years
Maximum \| Employee Stock Option
Stock Based Compensation Activity [Line Items]
Vesting period			3 years
Maximum \| Restricted (Nonvested) Stock
Stock Based Compensation Activity [Line Items]
Vesting period			3 years
Selling, general and administrative
Stock Based Compensation Activity [Line Items]
Compensation cost charged against income from share-based compensation plans					121
Restructuring Charges [Member]
Stock Based Compensation Activity [Line Items]
Compensation cost charged against income from share-based compensation plans					$ 39