Investments in Affiliates and Other Related Party Transactions - Amounts Recorded in Consolidated Balance Sheet for Affiliates (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Aggregate investment in affiliates	$ 108.2	$ 146.5
Receivables due from affiliates (including notes and advances)	141.1	140.7
Payables due to affiliates	$ 0.2	$ 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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