Derivative Financial Instruments (Offsetting Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative assets
Gross Amount Recognized	$ 112.6	$ 114.0
Gross Amounts Not Offset, But Permitted Under Master Netting Agreements	(105.7)	(105.9)
Net Amount	6.9	8.1
Derivative liabilities
Gross Amount Recognized	198.9	183.3
Gross Amounts Not Offset Permitted Under Master Netting Agreements	(105.7)	(105.9)
Net Amount	$ 93.2	$ 77.4

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.

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