Financial Instruments Investment Segment and Holding Company Narrative (Details) - Investment Funds [Member] - Investment Segment [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Derivative [Line Items]
Maximum payout amount relating to certain put options	$ 830		$ 5,900
Maximum payout amount relating to certain covered put options on existing short positions	830		5,900
Fair value derivative instruments with credit risk related contingent features in a liability position	467		33
Collateral for derivative positions	476		$ 883
Put Option [Member]
Derivative [Line Items]
Unrealized gains relating to certain put options	$ 10	$ 67

The maximum payout of the open option contracts written for the investment.

No definition available.

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- Definition

Open Option Contracts Written, Covered Put Options on Existing Short Positions

+ References

No definition available.

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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

Fair value of credit risk derivative liability.

+ 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 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5708775-113959

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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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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Details

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