Related Parties (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Accounts payable and accrued expenses related to adjustments to consideration of debt in connection with sale of business	$ 136.5	$ 143.5
WAVE [Member]
Related Party Transaction [Line Items]
Percentage of ownership in joint venture	50.00%
Purchases from joint venture	$ 21.5	22.5	$ 22.5
Reimbursement from joint venture	20.7	15.7	$ 15.8
Due to related parties	$ 4.9	3.3
Accounts payable and accrued expenses related to adjustments to consideration of debt in connection with sale of business		$ 25.9

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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-Name Accounting Standards Codification
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-SubTopic 10
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
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Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

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-Publisher FASB
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-Publisher FASB
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-Topic 850
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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