Debt tender offer to purchase up to $1.5 billion in aggregate principal

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- Definition

Line of Credit, Borrowing Capacity, Terminated

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Line of Credit Facility, Borrowing Capacity, Expired

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- Definition

Total Consideration of Debt Tender Offer

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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.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

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 - Additional Information (Detail) € in Millions, $ in Millions, ¥ in Billions	3 Months Ended				9 Months Ended
	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Jun. 30, 2019 JPY (¥)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 EUR (€)	Mar. 31, 2019 JPY (¥)	Sep. 30, 2016 USD ($)
Debt Instrument [Line Items]
Debt tender offer to purchase up to $1.5 billion in aggregate principal	$ 1,500.0
Total Consideration of Debt Tender Offer	1,600.0
Gain (Loss) on Extinguishment of Debt	60.0		$ 0.0		$ 60.0			$ 0.0
Notes Payable to Banks [Member] \| 5.25 percent due 2041 [Domain]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	$ 2.5				$ 2.5
Debt Instrument, Interest Rate, Stated Percentage	5.25%				5.25%				5.25%
Notes Payable to Banks [Member] \| Floating rate term loan [Domain]
Debt Instrument [Line Items]
Repayments of Debt \| ¥							¥ 10
Debt Instrument, Face Amount \| ¥										¥ 35
Notes Payable to Banks [Member] \| 1.375 percent due 2025 [Domain]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount \| €									€ 4.7
Debt Instrument, Interest Rate, Stated Percentage	1.375%				1.375%				1.375%
Notes Payable to Banks [Member] \| 3.9 percent due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount		$ 12.0
Debt Instrument, Interest Rate, Stated Percentage		3.90%								3.90%
Tyco International Holding S.a.r.L. (TSarL) [Member]
Debt Instrument [Line Items]
Repayments of Debt				$ 1,900.0
Long-term Debt											$ 4,000.0
Tyco International Holding S.a.r.L. (TSarL) [Member] \| Notes Payable to Banks [Member] \| $364 million due March 2020 [Domain]
Debt Instrument [Line Items]
Repayments of Debt					$ 364.0
Tyco International Holding S.a.r.L. (TSarL) [Member] \| Notes Payable to Banks [Member] \| $250 million USD expiring in Mar 2020 [Member]
Debt Instrument [Line Items]
Repayments of Debt					250.0
Tyco International Holding S.a.r.L. (TSarL) [Member] \| Notes Payable to Banks [Member] \| 215 million euro floating due July 2019 [Domain]
Debt Instrument [Line Items]
Repayments of Debt \| €						€ 215.0
Notes Payable to Banks [Member] \| $750 million term loan due earlier of Jan 2020 or 5 days after PS Close [Member]
Debt Instrument [Line Items]
Repayments of Debt					$ 750.0
Revolving Credit Facility [Member] \| Floating rate term loan [Domain]
Debt Instrument [Line Items]
Debt Instrument, Term	5 years
Revolving Credit Facility [Member] \| 250 million USD maturing in Mar 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 250.0
Revolving Credit Facility [Member] \| $250 million USD expiring in Mar 2020 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 250.0
Revolving Credit Facility [Member] \| 150 million USD maturing in Feb 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 150.0
Revolving Credit Facility [Member] \| $150 million USD expiring in February 2020 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 150.0
Revolving Credit Facility [Member] \| 200 million USD maturing in Jan 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 200.0
Revolving Credit Facility [Member] \| $350 million USD expiring in Jan 2020 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 350.0
Revolving Credit Facility [Member] \| Tyco International Holding S.a.r.L. (TSarL) [Member] \| $1.25 billion due August 2020 [Domain]
Debt Instrument [Line Items]
Line of Credit, Borrowing Capacity, Terminated	$ 1,250.0
Revolving Credit Facility [Member] \| Tyco International Holding S.a.r.L. (TSarL) [Member] \| $250 million USD expiring in Mar 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days