Investments in Affiliated Companies (Balance Sheet, Affiliates) (Details 5) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Summarized balance sheet for all affiliated companies
Current assets	$ 306.6	$ 144.8
Noncurrent assets	4,428.7	3,847.2
Total assets	4,735.3	3,992.0
Current liabilities	830.6	446.8
Noncurrent liabilities	3,013.0	2,704.9
Shareholders’ equity	891.7	840.3
Total liabilities and shareholders' equity	$ 4,735.3	$ 3,992.0

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