Number of persons employed by the Entity

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- Definition

Number of consolidated subsidiaries reported by the Company.

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- Definition

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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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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- Definition

Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.

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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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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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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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Related Party Transactions (Other Related Party Transactions) (Narrative) (Details)	3 Months Ended			6 Months Ended
	Jun. 30, 2017 USD ($) employee	Mar. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) employee	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items]
Distributions to non-controlling interests		$ 1,300,000		$ 1,280,000	$ 0
Management [Member] \| Subcontracting Arrangement, Construction Services [Member]
Related Party Transaction [Line Items]
Number of subsidiaries, non-controlling interests, subcontracting arrangement				1
Management [Member] \| Subcontracting Arrangement, Construction Services [Member] \| Related Contractor [Member]
Related Party Transaction [Line Items]
Number of additional management employees, subcontracting arrangement \| employee	2			2
Payments, related party	$ 15,000,000		$ 1,800,000	$ 15,500,000	3,300,000
Payables, related party	6,500,000			6,500,000		$ 100,000
Management [Member] \| Service Agreements [Member]
Related Party Transaction [Line Items]
Payments, related party	7,900,000		3,600,000	14,500,000	6,800,000
Payables, related party	3,900,000			3,900,000		3,700,000
Management [Member] \| Lease Agreements [Member]
Related Party Transaction [Line Items]
Payments, related party	14,400,000		9,900,000	27,100,000	19,100,000
Payables, related party	200,000			200,000		300,000
Executive Officers [Member] \| Employee Leasing Arrangements [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Charges, related party	200,000		200,000	400,000	400,000
Receivables, related party	200,000			200,000		200,000
Executive Officers [Member] \| Service Agreements [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Revenue, related party	200,000		200,000	400,000	400,000
Accounts receivable, related party	300,000			300,000		$ 400,000
Chairman, Board of Directors [Member] \| Lease Agreements [Member] \| Aircraft [Member]
Related Party Transaction [Line Items]
Payments, related party	500,000		$ 600,000	1,000,000	$ 1,300,000
Payables, related party	$ 0			$ 0