Related Parties (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Accounts payable and accrued expenses related to adjustments to consideration of debt in connection with sale of business	$ 148.7	$ 383.3
WAVE [Member]
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%
Purchases from joint venture	$ 22.5	22.5	$ 18.2
Reimbursement from joint venture	15.7	15.8	$ 14.9
Due from related parties	3.3	3.0
Accounts payable and accrued expenses related to adjustments to consideration of debt in connection with sale of business	$ 25.9	$ 22.4

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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