Investments (Details 9) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Change in Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Loss)
Change in unrealized net capital gains and losses	$ 2,668	$ 1,492	$ 3,708
Amount recognized for:
Insurance reserves	(177)	(585)	(9)
DAC and DSI	(288)	(209)	(731)
Amounts recognized	(465)	(794)	(740)
Deferred income taxes	(769)	(246)	(1,037)
Increase in unrealized net capital gains and losses	1,434	452	1,931
EMA limited partnerships
Change in Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Loss)
Change in unrealized net capital gains and losses	5	2
Fixed income securities
Change in Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Loss)
Change in unrealized net capital gains and losses	2,368	1,908	3,303
Equity securities
Change in Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Loss)
Change in unrealized net capital gains and losses	300	(423)	404
Derivatives
Change in Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Loss)
Change in unrealized net capital gains and losses	$ (5)	$ 5	$ 1

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Represents change in Deferred Policy Acquisition Costs and Deferred Sales Inducement Costs adjustment included in accumulated other comprehensive income (loss) during the period.

+ References

No definition available.

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- Definition

Represents change in insurance reserve adjustment included in accumulated other comprehensive income (loss) during the period.

+ References

No definition available.

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- Definition

Represents change in accumulated adjustments to Deferred Policy Acquisition Costs, Deferred Sales Inducement Costs, and insurance reserves related to unrealized capital gains and losses during the period.

+ References

No definition available.

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- Definition

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 21

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

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- Definition

The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

+ References

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- Definition

This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Paragraph 36

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 21

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 320

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