Investments in Affiliates and Other Related Party Transactions - Amounts Recorded in Consolidated Balance Sheet for Affiliates (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Aggregate investment in affiliates	$ 119.5	$ 108.2
Receivables due from affiliates (including notes and advances)	170.5	141.1
Payables due to affiliates	$ 0.1	$ 0.2

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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