Restructuring Costs, Other

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

+ Details

Name:	us-gaap_RestructuringReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

+ References

+ Details

Name:	us-gaap_RestructuringReserveSettledWithoutCash2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_EmployeeSeveranceMember
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- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=jci_FixedAssetImpairmentMember
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- Details

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Restructuring and Related Costs - Schedule of Restructuring Reserve by Type of Cost (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Restructuring Reserve [Abstract]
Restructuring and related costs	$ 57	$ 62	$ 144	$ 95
Current Restructuring Plans
Restructuring Reserve [Abstract]
Balance at September 30, 2025			44
Restructuring and related costs			73
Utilized—cash			(60)
Utilized—noncash			(33)
Other			18
Balance at March 31, 2026	42		42
Employee Severance and Termination Benefits \| Current Restructuring Plans
Restructuring Reserve [Abstract]
Balance at September 30, 2025			39
Restructuring and related costs			34
Utilized—cash			(58)
Utilized—noncash			0
Other			14
Balance at March 31, 2026	29		29
Long-Lived Asset Impairments \| Current Restructuring Plans
Restructuring Reserve [Abstract]
Balance at September 30, 2025			0
Restructuring and related costs			33
Utilized—cash			0
Utilized—noncash			(33)
Other			0
Balance at March 31, 2026	0		0
Other \| Current Restructuring Plans
Restructuring Reserve [Abstract]
Balance at September 30, 2025			5
Restructuring and related costs			6
Utilized—cash			(2)
Utilized—noncash			0
Other			4
Balance at March 31, 2026	$ 13		$ 13