Summary of Significant Accounting Policies - Schedule of Spot Trades (Details) - Spot Trade - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Accounts Receivable
Assets:
Gross	$ 1,629.9	$ 1,139.1
Offset on the Balance Sheet	(1,601.9)	(1,084.6)
Net	28.0	54.5
Accounts Payable
Liabilities:
Gross Liabilities	1,641.0	1,140.4
Offset on the Balance Sheet	(1,601.9)	(1,084.6)
Net Liabilities	$ 39.1	$ 55.8

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