Derivative Financial Instruments Offsetting Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Liability Collateral	$ 0.0	$ 0.0
Gross Amount Recognized	166.0	410.7
Gross Amounts Not Offset Permitted Under Master Netting Agreements	(33.3)	(57.9)
Net Amount	$ 132.7	$ 352.8

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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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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- References

No definition available.

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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
-Topic 210
-SubTopic 20
-Section 55
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- Definition

Fair value of securities pledged as collateral against derivative liabilities.

+ References

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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

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