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Debt and Financing Arrangements - Narrative (Details) € in Millions	1 Months Ended				9 Months Ended
	Mar. 31, 2023 EUR (€)	Jan. 31, 2023 USD ($)	Oct. 31, 2022 EUR (€)	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	May 31, 2023 EUR (€)	Mar. 31, 2023 USD ($)	Mar. 31, 2023 EUR (€)
Debt Instrument [Line Items]
Repayments of debt					$ 536,000,000	$ 3,000,000
4.625% Due in 2023
Debt Instrument [Line Items]
Repayments of debt		$ 32,000,000
Debt instrument, interest rate, stated percentage		4.625%
Corporate Bond Securities \| Johnson Controls International plc (JCI) and Tyco Fire & Security Finance S.C.A. (TFSCA)
Debt Instrument [Line Items]
Debt instrument, face amount					868,000,000		€ 800
Debt instrument, interest rate, stated percentage							4.25%
Term loans
Debt Instrument [Line Items]
Debt instrument, face amount								$ 163,000,000	€ 150
Term loans \| Euro Interbank Offered Rate (EURIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.40%
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt					0
$2.5 Billion Facility Expiring Dec 2024
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					2,500,000,000
$500 Million Facility Expiring Nov 2023
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					$ 500,000,000
Bank Term Loan Due October 2022 \| Term loans
Debt Instrument [Line Items]
Repayments of short-term debt			€ 200	$ 196,000,000
Bank Term Loan Due October 2022 \| Term loans \| Euro Interbank Offered Rate (EURIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			0.50%
Bank Term Loan Due April 2024 \| Term loans
Debt Instrument [Line Items]
Debt instrument, face amount			€ 150					$ 163,000,000
Bank Term Loan Due April 2024 \| Euro Interbank Offered Rate (EURIBOR) \| Term loans
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			0.70%
Euro Bank 150M Term Loan \| Term loans
Debt Instrument [Line Items]
Repayments of debt	€ 150			147,000,000
Debt instrument, interest rate, stated percentage								0.00%	0.00%
Euro Bank 135M Term Loan \| Term loans
Debt Instrument [Line Items]
Repayments of debt	€ 135			$ 133,000,000
Euro Bank 135M Term Loan \| Euro Interbank Offered Rate (EURIBOR) \| Term loans
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%