Deferred Policy Acquisition Costs and Value of Business Acquired (Details Textuals) (USD $)	12 Months Ended
Dec. 31, 2011
Estimated future amortization expense allocated to other expenses for VOBA
Estimated future amortization expense allocated to other expenses for VOBA in 2012	$ 1,300,000,000
Estimated future amortization expense allocated to other expenses for VOBA in 2013	1,100,000,000
Estimated future amortization expense allocated to other expenses for VOBA in 2014	917,000,000
Estimated future amortization expense allocated to other expenses for VOBA in 2015	774,000,000
Estimated future amortization expense allocated to other expenses for VOBA in 2016	$ 661,000,000

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Expected amortization expense in the fifth year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 92-9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section S99

-Paragraph 2

-Subparagraph (3)

-URI http://asc.fasb.org/extlink&oid=6784649&loc=d3e569990-122904

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- Definition

Expected amortization expense in the fourth year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

+ Details

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- Definition

Expected amortization expense in the first year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

+ Details

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- Definition

Expected amortization expense in the third year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

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- Definition

Expected amortization expense in the second year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

+ Details

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