Line of Credit Facility, Borrowing Capacity, Expired

No definition available.

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Period Type:	duration

- Definition

Transactions costs related to debt exchange offers

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Period Type:	instant

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Details

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- Details

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- Details

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- Details

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Debt and Financing Arrangements - Additional Information (Detail) € in Millions, $ in Millions	3 Months Ended			6 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 EUR (€)	Mar. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Debt Instrument [Line Items]
Transactions costs related to debt exchange offers				$ 17
Tyco International Holding S.a.r.L. (TSarL) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 1,250				$ 1,000
Three Point Seven Five Percent Due 2018 [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 67
Interest Rate Terms	0.0375
150 million euro floating rate term loan maturing in September 2018 [Member]
Debt Instrument [Line Items]
Repayments of Debt \| €			€ 150
Debt Instrument, Term		364 days	364 days
One Point Four Percent Due Two Thousand Eighteen
Debt Instrument [Line Items]
Repayments of Debt		$ 300
Interest Rate Terms		0.014	0.014
Unsecured Debt [Member] \| Zero Point Zero Percent Due Two Thousand Twenty-One [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €			€ 750
Interest Rate Terms		0.0	0.0
Tyco International Holding S.a.r.L. (TSarL) [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 26	$ 1,900
Long-term Debt	$ 1,700					$ 4,000
Revolving Credit Facility [Member] \| 250 million USD maturing in Mar 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	364 days
Debt Instrument, Face Amount	$ 250
Revolving Credit Facility [Member] \| 150 million USD maturing in Mar 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	364 days
Line of Credit Facility, Borrowing Capacity, Expired	$ 150
Revolving Credit Facility [Member] \| 150 million USD maturing in Feb 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	364 days
Line of Credit Facility, Borrowing Capacity, Expired	$ 150
Revolving Credit Facility [Member] \| 150 million USD maturing in Feb 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 150
Revolving Credit Facility [Member] \| 250 million USD maturing in Jan 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	364 days
Line of Credit Facility, Borrowing Capacity, Expired	$ 250
Revolving Credit Facility [Member] \| 200 million USD maturing in Jan 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 200