Deferred Policy Acquisition Costs, Value of Business Acquired and Other Policy-Related Intangibles (Estimated Future Amortization) (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Estimated future amortization expense allocated to other expenses for VOBA [Abstract]
VOBA 2017	$ 108
VOBA 2018	92
VOBA 2019	78
VOBA 2020	58
VOBA 2021	50
Value of Distribution Agreements and Customer Relationships Acquired [Abstract]
VODA and VOCRA 2017	14
VODA and VOCRA 2018	13
VODA and VOCRA 2019	12
VODA and VOCRA 2020	11
VODA and VOCRA 2021	$ 9

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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 Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section S99
-Paragraph 2
-Subparagraph (3)
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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.

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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.

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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.

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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.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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