Debt and Financing Arrangements - Narrative (Details) - USD ($) |
1 Months Ended | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|---|
Feb. 28, 2026 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Debt Instrument [Line Items] | |||||
| Debt repayments | $ 639,000,000 | $ 1,096,000,000 | |||
| Foreign currency exchange derivatives | Income Statement Location [Axis]: jci:NetFinancingCharges | |||||
| Debt Instrument [Line Items] | |||||
| Amount of (loss) recognized in income on derivative | $ (33,000,000) | $ 71,000,000 | (222,000,000) | $ (13,000,000) | |
| $2.5 Billion Facility Expiring Dec 2024 | |||||
| Debt Instrument [Line Items] | |||||
| Line of credit facility, maximum borrowing capacity | 2,500,000,000 | 2,500,000,000 | |||
| Notes 3.90 Percent Due 2026 | Senior Notes | |||||
| Debt Instrument [Line Items] | |||||
| Debt repayments | $ 538,000,000 | ||||
| Debt instrument, interest rate, stated percentage | 3.90% | ||||
| Revolving Credit Facility | |||||
| Debt Instrument [Line Items] | |||||
| Long-term debt | $ 0 | $ 0 | |||
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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