Represents the number of subsidiaries of the entity to whom the County sent a letter.

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Represents the number of defendants against whom suit was filed to seek reimbursement for the cost of remediating environmental contamination.

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Represents the number of potentially responsible parties including the entity, who were advised of their potential liability for the clean-up costs of the contamination that is the subject of the County Suit.

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Represents the number of subsidiaries of the entity, which were involved in the dispute.

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Amount of minimum lease payments after the fourth full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of minimum lease payments within the first full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of minimum lease payments within the fourth full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of minimum lease payments within the remainder of the fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of minimum lease payments within the second full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of minimum lease payments within the third full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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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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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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The total of future contractually required payments on leases defined as operating.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Commitments and Contingencies (Details) (USD $)	3 Months Ended		9 Months Ended		1 Months Ended	9 Months Ended
Commitments and Contingencies (Details) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Apr. 30, 2001 Miami Airport Litigation party person subsidiary	Sep. 30, 2011 Brendan Airways Litigation subsidiary
Legal Matters
Number of defendants (in persons)					17
Number of Potentially Responsible Parties					250
Number of subsidiaries that received a letter					1
Number of subsidiaries involved in dispute						1
Damages sought by Brendan, plus interest and attorney's fees						$ 4,500,000
Future minimum lease payments under non-cancelable operating leases
2011 (3 months)	5,271,000		5,271,000
2012	18,484,000		18,484,000
2013	16,394,000		16,394,000
2014	15,435,000		15,435,000
2015	14,150,000		14,150,000
Thereafter	40,200,000		40,200,000
Total future minimum lease payment	109,934,000		109,934,000
Rental expenses for properties and equipment	$ 4,700,000	$ 2,500,000	$ 13,200,000	$ 7,200,000