Derivative Financial Instruments - Fair Value of Derivaitves (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Derivatives, fair value disclosures
Derivative instruments, assets	$ 1,291.6	$ 666.6
Derivative instruments, liabilities	1,536.6	1,180.1
Fair value of embedded derivative liabilities reported with contractholder funds	324.3	177.4
Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	97.0	103.5
Derivative instruments, liabilities	272.9	296.4
Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	1,194.6	563.1
Derivative instruments, liabilities	1,263.7	883.7
Interest rate contracts \| Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	18.5	9.4
Derivative instruments, liabilities	136.8	132.2
Interest rate contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	1,071.8	493.0
Derivative instruments, liabilities	536.6	255.8
Foreign exchange contracts \| Derivatives designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	78.5	94.1
Derivative instruments, liabilities	136.1	164.2
Foreign exchange contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	30.8	16.4
Derivative instruments, liabilities	61.6	68.1
Equity contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	83.4	39.8
Derivative instruments, liabilities	91.0	112.3
Credit contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, assets	8.6	13.9
Derivative instruments, liabilities	22.8	39.7
Other contracts \| Derivatives not designated as hedging instrument
Derivatives, fair value disclosures
Derivative instruments, liabilities	$ 551.7	$ 407.8

This item represents the fair value of embedded derivatives that have been bifurcated from an investment 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=51824906&loc=SL20225862-175312

+ Details

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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

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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