Managed Investment Entities (Details Textuals) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Variable Interest Entity [Line Items]
Assets of managed investment entities	$ 2,591	$ 2,537
Liabilities of managed investment entities	2,430	2,323
Appropriated - managed investment entities	142	197
Managed Investment Entities (Textuals) [Abstract]
Percentage of investment of most subordinate debt tranche, Minimum	7.50%
Percentage of investment of most subordinate debt tranche, Maximum	24.40%
Number of collateralized loan obligation entities	6
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	60	69
Difference between aggregate unpaid principal balance and fair value of CLOs' debt	229	301
Aggregate unpaid principal balance of CLO loans in default	18	12
Carrying amount of CLO loans in default	6	6
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Aggregate fair value of collateralized loan obligations	19
CLO expected to be liquidated [Member]
Variable Interest Entity [Line Items]
Assets of managed investment entities	498
Liabilities of managed investment entities	480
Appropriated - managed investment entities	$ 18

Aggregate unpaid principal balance of variable interest entity loans in default.

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Carrying amount of variable interest entity loans in default.

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Difference between aggregate unpaid principal balance and fair value of variable interest entity debt.

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Difference between aggregate unpaid principal balance and fair value of variable interest entity investments.

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- Definition

Managed investment entities.

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Number of collateralized loan obligation entities.

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- Definition

Maximum percentage of investment of most subordinate debt tranche of variable interest entity.

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Minimum percentage of investment of most subordinate debt tranche of variable interest entity.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Available-for-Sale Securities
-URI http://asc.fasb.org/extlink&oid=6505594

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-Publisher FASB
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-Paragraph 13
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
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-Publisher SEC
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-Article 7
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- Definition

A segregation of retained earnings which is unavailable for dividend distribution. Includes also retained earnings appropriated for loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.30(a)(3)(i))
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 7
-Section 03
-Paragraph 24
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+ Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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-Name Accounting Standards Codification
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-Paragraph 3
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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

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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.

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