Affiliated Equity - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Affiliate Equity [Line Items]
Distributions paid to affiliate partners	$ 104.6	$ 112.4
Payments to acquire interest in affiliates	15.4	14.5
Issuance of interest in affiliates	9.4	$ 6.2
Other Assets
Affiliate Equity [Line Items]
Due from affiliates	15.0		$ 16.2
Other Liabilities
Affiliate Equity [Line Items]
Due to affiliates	$ 75.4		$ 36.2

[Line Items] for Affiliate Equity [Table]

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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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