Intangible Assets (Estimated Amortization Expense Over Next Five Years) (Details) $ in Millions	Dec. 31, 2015 USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2016, Other intangible assets	$ 88
2017, Other intangible assets	78
2018, Other intangible assets	70
2019, Other intangible assets	63
2020, Other intangible assets	58
Total, Other intangible assets	357
2017, VOBA	35
2016, VOBA	39
2018, VOBA	32
2019, VOBA	27
2020, VOBA	24
Total, VOBA	$ 157

Total amortization expected to be recognized for finite lived intangible assets over the next five years.

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- Definition

Total amortization expense estimated to be recorded over the next five years for intangible assets arising from insurance contracts acquired in business combinations

+ References

No definition available.

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- Definition

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)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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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.

+ References

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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 fourth 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

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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.

+ References

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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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- Definition

Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for intangible assets arising from insurance contracts acquired in a business combination.

+ 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)
-URI http://asc.fasb.org/extlink&oid=27015749&loc=d3e569990-122904

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for intangible assets arising from insurance contracts acquired in a business combination.

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for intangible assets arising from insurance contracts acquired in a business combination.

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for intangible assets arising from insurance contracts acquired in a business combination.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for intangible assets arising from insurance contracts acquired in a business combination.

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