Investment in Unconsolidated Affiliates Summarized Balance Sheet Information of Equity Method Investment (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Summarized Balance Sheet Information of Equity Method Investment [Abstract]
Current assets	$ 333.0	$ 389.0
Non-current assets	11,784.0	11,877.0
Current liabilities	391.0	780.0
Non-current liabilities	$ 4,374.0	$ 4,077.0

Summarized Balance Sheet Information of Equity Method Investment [Abstract]

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The amount of current assets reported by an equity method investment of the entity.

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