Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Derivative, amount of hedged ordinary shares

+ References

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- Definition

Gains (losses) reclassified from CTA to income for the Company's outstanding net investment hedges

+ References

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- Definition

Hedge percentage for foreign exchange transactional exposures, Maximum.

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- Definition

Hedge percentage for foreign exchange transactional exposures, Minimum.

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- Definition

Number of forward treasury lock agreements terminated.

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Number of forward treasury lock agreements.

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- Definition

Types of Notes Forward Treasury Lock Agreements Fixed Portion of Future Interest Cost

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624258-113959

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- Definition

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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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

Number of interest rate derivative instruments held by the entity at the reporting date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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Derivative Instruments and Hedging Activities - Additional Information (Detail) € in Millions, shares in Millions, ¥ in Billions	3 Months Ended			9 Months Ended
	Jun. 30, 2017 USD ($) Swap shares	Jun. 30, 2016 USD ($)	Sep. 30, 2005 USD ($) Agreement	Jun. 30, 2017 USD ($) Swap	Jun. 30, 2016 USD ($)	Jun. 30, 2017 EUR (€) Swap	Sep. 30, 2016 USD ($) Swap	Sep. 30, 2016 EUR (€) Swap	Sep. 30, 2016 JPY (¥) Swap	Mar. 31, 2006 Agreement
Derivative [Line Items]
Hedge percentage for foreign exchange transactional exposures, Minimum				70.00%
Hedge percentage for foreign exchange transactional exposures, Maximum				90.00%
Number of fixed to floating interest rate swaps outstanding \| Swap	0			0		0	8	8	8
Derivative, amount of hedged ordinary shares \| shares	1.4
Number of forward treasury lock agreements \| Agreement			3
Types Of Notes Forward Treasury Lock Agreements Fixed Portion Of Future Interest Cost			5-year, 10-year and 30-year notes
Number of forward treasury lock agreements terminated \| Agreement										3
Collateral posted	$ 0			$ 0			$ 0
Gains (losses) reclassified from CTA to income for the Company's outstanding net investment hedges	0	$ 0		0	$ 0
Gains (losses) recognized in income for the ineffective portion of cash flow hedges	0	0		0	0
Equity swap
Derivative [Line Items]
Derivative, Amount of Hedged Item							$ 0
Treasury Lock
Derivative [Line Items]
Notional amount			$ 1,300,000,000
Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount \| ¥									¥ 37
One billion euro net investment hedge [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount \| €						€ 1,000		€ 1,000
500 million euro net investment hedge [Member] [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount \| €						€ 485		€ 500
Net Investment Hedging [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ (105,000,000)	$ (36,000,000)		$ (77,000,000)	$ (62,000,000)