Derivative Financial Instruments Offsetting Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Offsetting Derivative Liabilities [Abstract]
Derivative Liability Collateral	$ 0	$ 0
Gross Amount Recognized	633.7	450.4
Gross Amounts Not Offset Permitted Under Master Netting Agreements	(430.6)	(321.5)
Net Amount	$ 203.1us-gaap_DerivativeLiabilities	$ 128.9us-gaap_DerivativeLiabilities

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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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-Publisher FASB

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Fair value, after the 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 not elected to be offset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Fair value of securities pledged as collateral against derivative liabilities.

+ References

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- Definition

Fair value of 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, elected not to be offset, deducted from derivative liabilities.

+ References

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

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