Related Party Transactions (Executive Officers) (Narrative) (Details)	3 Months Ended
Mar. 31, 2021 USD ($) numberOfEmployees	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Management [Member] \| Subcontracting Arrangements [Member]
Related Party Transaction [Line Items]
Number of management members, subcontracting arrangement \| numberOfEmployees	2
Expenses, related party	$ 29,000,000.0	$ 700,000
Payables, related party	18,600,000		$ 1,400,000
Chairman, Board of Directors [Member] \| Lease Agreements [Member]
Related Party Transaction [Line Items]
Expenses, related party	600,000	600,000
Executive Officers [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Receivables, related party	800,000		900,000
Charges, related party	300,000	300,000
Executive Officers [Member] \| Construction Services [Member]
Related Party Transaction [Line Items]
Expenses, related party	100,000	200,000
Payables, related party	$ 0		$ 0
Revenue, related party		$ 4,000,000.0

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Amount for accounts payable to related parties.

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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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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