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

Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

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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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Fair Value Measurements - Additional Information (Detail) € in Millions, $ in Millions, ¥ in Billions	Jun. 30, 2017 USD ($)	Jun. 30, 2017 EUR (€)	Sep. 30, 2016 USD ($)	Sep. 30, 2016 EUR (€)	Sep. 30, 2016 JPY (¥)
Derivative [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax	$ 5		$ (1)
Fair value of long term debt	12,600		15,700
Fair Value, Inputs, Level 1 [Member]
Derivative [Line Items]
Fair value of long term debt	8,700		9,700
Fair Value, Inputs, Level 2 [Member]
Derivative [Line Items]
Fair value of long term debt	$ 3,900		$ 6,000
Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount \| ¥					¥ 37
Foreign Currency Denominated Debt [Member] \| One billion euro net investment hedge [Member]
Derivative [Line Items]
Notional amount \| €		€ 1,000		€ 1,000
Foreign Currency Denominated Debt [Member] \| 500 million euro net investment hedge [Member] [Member]
Derivative [Line Items]
Notional amount \| €		€ 485		€ 500