Summary of Significant Accounting Policies - Schedule of Spot Trades (Details) - Spot Trade - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accounts Receivable
Assets:
Gross	$ 1,461.7	$ 1,139.1
Offset on the Balance Sheet	(1,421.8)	(1,084.6)
Net Assets	39.9	54.5
Accounts Payable
Liabilities:
Gross Liabilities	1,455.1	1,140.4
Offset on the Balance Sheet	(1,421.8)	(1,084.6)
Net Liabilities	$ 33.3	$ 55.8

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