Derivative Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivatives, fair value disclosures
Total derivative instruments, assets	$ 661.8	$ 665.1
Total derivative instruments, liabilities	1,207.3	1,248.7
Fair value of embedded derivative liabilities reported with contractholder funds	176.4	6.9
Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	88.8	121.7
Total derivative instruments, liabilities	263.0	336.6
Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	573.0	543.4
Total derivative instruments, liabilities	944.3	912.1
Interest rate contracts \| Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	8.8	0.1
Total derivative instruments, liabilities	193.9	285.4
Interest rate contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	508.7	452.2
Total derivative instruments, liabilities	321.4	489.6
Foreign exchange contracts \| Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	80.0	121.6
Total derivative instruments, liabilities	69.1	51.2
Foreign exchange contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	20.8	51.6
Total derivative instruments, liabilities	40.1	17.9
Equity contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	30.2	30.0
Total derivative instruments, liabilities	131.7	145.0
Credit contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, assets	13.3	9.6
Total derivative instruments, liabilities	35.6	35.5
Other contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Total derivative instruments, liabilities	$ 415.5	$ 224.1

This item represents the fair value of embedded derivatives that have been bifurcated from an investment-type insurance host contract.

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

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