Summary of Significant Accounting Policies Summary of Significant Accounting Policies - Schedule of Spot Trades (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative Asset [Abstract]
Gross	$ 114.9	$ 109.5
Net	72.1	68.8
Derivative Liability [Abstract]
Gross	103.8	112.9
Net	60.9	72.1
Accounts Receivable \| Spot Trade
Derivative Asset [Abstract]
Gross	1,139.1	815.7
Offset on the Balance Sheet	(1,084.6)	(745.2)
Net	54.5	70.5
Accounts Payable \| Spot Trade
Derivative Liability [Abstract]
Gross	1,140.4	760.8
Offset on the Balance Sheet	(1,084.6)	(745.2)
Net	$ 55.8	$ 15.6

Fair value of liability associated with 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.

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