Debt Instrument, Interest Rate Increase, Condition 1 Not Met

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- Definition

Debt Instrument, Interest Rate Increase, Condition 2 Not Met

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

+ References

No definition available.

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

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Debt and Financing Arrangements Financing Arrangements (Details)	12 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 EUR (€)	Sep. 30, 2021 EUR (€)
Notes 3.750 Percent Due 2021 [Domain]
Debt Instrument [Line Items]
Repayments of Debt	$ 193,000,000
Interest rate on notes	3.75%		3.75%
Bank term loan due March 2022
Debt Instrument [Line Items]
Repayments of Debt \| €		€ 200,000,000
Notes 4.250 Percent Due 2021 [Domain]
Debt Instrument [Line Items]
Repayments of Debt	$ 257,000,000
Interest rate on notes	4.25%		4.25%
Notes 1.000 Percent Due 2023 [Domain]
Debt Instrument [Line Items]
Repayments of Debt \| €		€ 43,000,000
Interest rate on notes	1.00%		1.00%
Johnson Controls International plc [Member] \| Three Point Six Two Five Percent Due Two Thousand Twenty Four [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 453,000,000
Interest rate on notes	3.625%		3.625%
Johnson Controls International plc [Member] \| Four Point Nine Five Percent Due Two Thousand Sixty Four [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 341,000,000
Interest rate on notes	4.95%		4.95%
Johnson Controls International plc (JCI) and Tyco Fire & Security Finance S.C.A. (TFSCA) \| Zero Point Three Seven Five Percent Due Two Thousand Twenty Seven
Debt Instrument [Line Items]
Debt instrument, face amount \| €			€ 500,000,000
Interest rate on notes	0.375%		0.375%
Johnson Controls International plc (JCI) and Tyco Fire & Security Finance S.C.A. (TFSCA) \| One Point Zero Percent Due Two Thousand Thirty Two
Debt Instrument [Line Items]
Debt instrument, face amount \| €			€ 500,000,000
Interest rate on notes	1.00%		1.00%
Johnson Controls International plc (JCI) and Tyco Fire & Security Finance S.C.A. (TFSCA) \| One Point Seven Five Percent Due Two Thousand Thirty
Debt Instrument [Line Items]
Debt instrument, face amount	$ 625,000,000
Interest rate on notes	1.75%		1.75%
Johnson Controls International plc (JCI) and Tyco Fire & Security Finance S.C.A. (TFSCA) \| Two Point Zero Percent Due Two Thousand Thirty One
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000,000
Interest rate on notes	2.00%		2.00%
Debt Instrument, Interest Rate Increase, Condition 1 Not Met	0.125%	0.125%
Debt Instrument, Interest Rate Increase, Condition 2 Not Met	0.125%	0.125%