Number of persons employed by the Entity

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- Definition

Amount for accounts payable to related parties.

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- Definition

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

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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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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Related Party Transactions (Executive Officers) (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Management [Member] \| Subcontracting Arrangements [Member]
Related Party Transaction [Line Items]
Number of additional management employees, subcontracting arrangement \| employee	2		2
Payments or expenses, related party	$ 0.0	$ 4.6	$ 0.6	$ 6.2
Payables, related party	0.2		0.2		$ 0.2
Chairman, Board of Directors [Member] \| Lease Agreements [Member]
Related Party Transaction [Line Items]
Payments or expenses, related party	0.6	0.7	1.3	1.4
Executive Officers [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Receivables, related party	0.9		0.9		0.8
Charges, related party	0.3	0.4	0.7	0.7
Executive Officers [Member] \| Construction Services [Member]
Related Party Transaction [Line Items]
Payments or expenses, related party			0.2
Revenue, related party	1.5	$ 2.3	5.5	$ 2.3
Receivables, related party	$ 3.1		$ 3.1		$ 3.9