Investments (Details 14) (USD $) In Millions	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Changes in fixed maturity securities with noncredit OTTI losses in accumulated other comprehensive income (loss)
Balance, beginning of period	$ (601)	$ (859)
Noncredit OTTI losses recognized	(184)	(212)
Transferred to retained earnings	0	16
Securities sold with a previous noncredit OTTI loss	77	137
Subsequent increases in estimated fair value	(31)	317
Balance, end of period	$ (739)	$ (601)

- Definition

This item presents the change in accumulated other comprehensive income (loss) from securities sold with a previous noncredit OTTI loss.

+ Details

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- Definition

This item presents the increase (decrease) in estimated fair value of fixed maturity securities with noncredit OTTI losses that were previously recognized in accumulated other comprehensive loss.

+ Details

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- Definition

Changes in fixed maturity securities with noncredit OTTI losses in accumulated other comprehensive income (loss).

+ Details

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- Definition

This item presents the noncredit OTTI losses on fixed maturity securities recognized during the reporting period included in accumulated other comprehensive loss.

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- Definition

Noncredit OTTI losses transferred to retained earnings related to adoption of new guidance related to consolidation of variable interest entities.

+ Details

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- Definition

Other-than-temporary impairments on fixed maturity securities transferred to other comprehensive income loss.

+ Details

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