Acquisitions and Divestitures - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Acquisitions And Divestitures [Line Items]
Business divestitures, net of cash divested	$ 11	$ 0
Goodwill, Written off Related to Sale of Business Unit	4
Cash paid for business acquisition	0	48
Goodwill, Acquired During Period	0
Building Solutions Asia Pacific
Acquisitions And Divestitures [Line Items]
Goodwill, Written off Related to Sale of Business Unit	4
Goodwill, Acquired During Period	0
Global Products
Acquisitions And Divestitures [Line Items]
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Acquired During Period	0
Building Solutions EMEA/LA
Acquisitions And Divestitures [Line Items]
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Acquired During Period	0
Individually Immaterial Acquisitions
Acquisitions And Divestitures [Line Items]
Purchase price, net of cash acquired		54
Cash paid for business acquisition		48
Individually Immaterial Acquisitions \| Global Products
Acquisitions And Divestitures [Line Items]
Goodwill, Acquired During Period		17
Individually Immaterial Acquisitions \| Building Solutions EMEA/LA
Acquisitions And Divestitures [Line Items]
Goodwill, Acquired During Period		$ 12
Business Divestitures, Not Specific [Member] \| Building Solutions Asia Pacific
Acquisitions And Divestitures [Line Items]
Proceeds from Divestiture of Businesses	15
Business divestitures, net of cash divested	11
Goodwill, Written off Related to Sale of Business Unit	$ 4

Acquisitions And Discontinued Operations [Line Items]

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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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.

+ References

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-Publisher FASB
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-Section 50
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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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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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 12
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