Investments in Affiliates and Other Related Party Transactions - Amounts Recorded in Consolidated Balance Sheet for Affiliates (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Aggregate investment in affiliates	$ 142.9	$ 119.5
Receivables due from affiliates (including notes and advances)	142.0	170.5
Payables due to affiliates	$ 1.6	$ 0.1

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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