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Affiliate Equity - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Affiliate Equity
Distributions paid to affiliate partners	$ 306.3	$ 347.9	$ 370.5
Payments to acquire interest in affiliates	315.1	146.0	120.0
Issuance of interest in affiliates	20.2	10.5	$ 6.3
Other Assets
Affiliate Equity
Due from affiliates	9.6	14.8
Other Liabilities
Affiliate Equity
Due to affiliates	$ 22.0	$ 19.8
Minimum
Affiliate Equity
Affiliate equity, conditional right to put interest, period	5 years
Maximum
Affiliate Equity
Affiliate equity, conditional right to put interest, period	15 years

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Affiliate Equity, Conditional Right to Put Interest, Period

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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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