Derivative Financial Instruments (Offsetting Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Derivative assets
Gross Amount Recognized	$ 168.5	$ 173.2
Gross Amounts Not Offset, But Permitted Under Master Netting Agreements	(146.5)	(114.4)
Net Amount	22.0	58.8
Derivative liabilities
Gross Amount Recognized	186.2	137.1
Gross Amounts Not Offset Permitted Under Master Netting Agreements	(146.5)	(114.4)
Net Amount	$ 39.7	$ 22.7

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 55
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+ References

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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.

+ References

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