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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Derivative, amount of hedged ordinary shares

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Gains (Losses) Reclassifed from CTA to Income for Outstanding Net Investment Hedges

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Hedge percentage for foreign exchange transactional exposures, Maximum.

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Number of interest rate derivatives terminated

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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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.

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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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The increase (decrease) during the reporting period in the amount of cash that is received as security when loaning securities.

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

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Derivative Instruments and Hedging Activities Derivatives, Additional Information (Details) € in Millions, shares in Millions, ¥ in Billions	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2018 USD ($) Swap shares	Sep. 30, 2017 USD ($) shares	Sep. 30, 2016 USD ($) Swap	Sep. 30, 2018 EUR (€) Swap	Sep. 30, 2018 JPY (¥) Swap	Sep. 30, 2017 EUR (€)	Sep. 30, 2017 JPY (¥)
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability		$ 3,175,000,000	$ 2,105,000,000
Increase (Decrease) in Cash Collateral for Loaned Securities		$ 0	$ 0
Hedge percentage for foreign exchange transactional exposures, Minimum		70.00%
Hedge percentage for foreign exchange transactional exposures, Maximum		90.00%
Derivative, amount of hedged ordinary shares \| shares		1.8	1.4
Number of fixed to floating interest rate swaps outstanding \| Swap		0			0	0
Number of interest rate derivatives terminated	4
Gains (Losses) recognized in income for the ineffective portion of cash flow hedges			$ 0	$ 0
Gains (Losses) Reclassifed from CTA to Income for Outstanding Net Investment Hedges		$ 0	0	0
1.4% Due in 2018
Derivative [Line Items]
Interest rate on notes		1.40%			1.40%	1.40%
Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability		$ 3,173,000,000	2,080,000,000
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability		2,000,000	25,000,000
Interest rate swaps \| Two Point Six Percent Due Two Thousand Seventeen
Derivative [Line Items]
Derivative, Amount of Hedged Item				$ 400,000,000
Number of fixed to floating interest rate swaps outstanding \| Swap				4
Interest rate on notes				2.60%
Interest rate swaps \| 1.4% Due in 2018
Derivative [Line Items]
Derivative, Amount of Hedged Item				$ 300,000,000
Number of fixed to floating interest rate swaps outstanding \| Swap				3
Interest rate on notes				1.40%
Interest rate swaps \| 7.125 % Due in 2017
Derivative [Line Items]
Derivative, Amount of Hedged Item				$ 150,000,000
Number of fixed to floating interest rate swaps outstanding \| Swap				1
Interest rate on notes				7.125%
Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| ¥						¥ 35		¥ 35
Equity swap
Derivative [Line Items]
Derivative, Amount of Hedged Item		73,000,000	58,000,000
One billion euro net investment hedge [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €					€ 1,000		€ 1,000
750 million euro net investment hedge [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €					750
423 million euro net investment hedge [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €					423
58 million euro net investment hedge [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €					58		58
215 million EUR maturing in March 2020 [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €					€ 215
500 million euro net investment hedge [Member] [Member] \| Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Derivative, Notional Amount \| €							€ 423
Net Investment Hedging [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net		$ 45,000,000	$ (138,000,000)	$ (82,000,000)