Number of persons employed by the Entity

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Number of consolidated subsidiaries reported by the Company.

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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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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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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) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) employee	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) employee	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Management [Member] \| Subcontracting Arrangement, Ancillary Services [Member]
Related Party Transaction [Line Items]
Number of additional management employees, subcontracting arrangement \| employee	2		2
Expenses from transactions with related party	$ 1.8		$ 3.3
Accounts payable, related party	$ 1.0		1.0
Management [Member] \| Subcontracting Arrangement, Ancillary Services [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Number of subsidiaries	1
Management [Member] \| Service Agreements [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 3.6	$ 0.5	6.8	$ 1.4
Accounts payable, related party	1.7		1.7		$ 2.1
Management [Member] \| Lease Agreements [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	9.9	4.1	19.1	9.4
Accounts payable, related party	0.2		0.2		0.1
Executive Officers [Member] \| Employee Leasing Arrangements [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Charges, related party	0.2	0.2	0.4	0.4
Due from related party	0.2		0.2		0.1
Executive Officers [Member] \| Service Agreements [Member] \| Related Customer [Member]
Related Party Transaction [Line Items]
Revenue, related party	0.2	$ 0.2	0.4	$ 0.4
Accounts receivable, related party	0.4		0.4		$ 0.3
Chairman, Board of Directors [Member] \| Lease Agreements [Member] \| Aircraft [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 0.6		$ 1.3