Acquisitions And Discontinued Operations [Line Items]

No definition available.

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- Definition

Number of businesses divested.

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No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

Reduction in cash due to no longer including the former subsidiary's cash in the consolidated entity's cash.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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- Definition

The net cash inflow or outflow associated with the aggregate amount of adjustment to the purchase price of a previous acquisition.

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

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Acquisitions and Divestitures - Additional Information (Detail) $ in Millions	3 Months Ended			6 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition				$ 15	$ 6
Goodwill, Acquired During Period				8
Proceeds from business divestitures, net of cash divested				2,114	180
Reduction in goodwill related to business divestitures				20
Adjustment to purchase price of previous acquisition				0	37
Scott Safety business [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested		$ 2,000
Reduction in goodwill related to business divestitures		1,200
Gain on sale of Scott Safety business		114
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax		84
Business Divestitures, Not Specific [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested					52
Proceeds from Divestiture of Businesses					$ 4
Number Of Businesses Divested					1
Cash Divested from Deconsolidation					$ 5
Individually Immaterial Acquisitions
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition					$ 6
Number of acquisitions					3
Purchase price, net of cash acquired					$ 9
Global Products \| Business Divestitures, Not Specific [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested	$ 103
Reduction in goodwill related to business divestitures	20
Global Products \| Individually Immaterial Acquisitions
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition				15
Goodwill, Acquired During Period				8
Building Solutions EMEA/LA \| ADT security business in South Africa [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested			$ 129
Reduction in goodwill related to business divestitures			$ 92
Power Solutions
Acquisitions And Discontinued Operations [Line Items]
Goodwill, Acquired During Period				0
Reduction in goodwill related to business divestitures				0
Tyco International Holding S.a.r.L. (TSarL) [Member]
Acquisitions And Discontinued Operations [Line Items]
Repayments of Debt	26	$ 1,900
Long-term Debt	$ 1,700			$ 1,700		$ 4,000