Financial Instruments (Counterparty credit risk) (Details) $ in Millions	Sep. 30, 2015 USD ($)
Counterparty credit risk
Total Collateral Received	$ 4,354
Fair value of collateral posted to counterparties for derivative obligations	895
Exposure To Counterparties Including Interest Net Collateral Excluding Derivatives	674
Cash [Member]
Counterparty credit risk
Total Collateral Received	2,844
Securities Held By Third Parties [Member]
Counterparty credit risk
Securities Held as Collateral, at Fair Value	$ 1,510

The fair value of total collateral posted by counter parties in master netting agreements. Includes cash and security amounts.

No definition available.

+ Details

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- Definition

The amount of the Company's exposure to counterparties, including interest due, net of collateral held, but excluding embedded derivatives

+ References

No definition available.

+ Details

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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=56946850&loc=SL5624258-113959

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- References

No definition available.

+ Details

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- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5086-111524

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- Details

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- Details

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