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Represents the amount of interest income and expense, net, which includes other financing costs.

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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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Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Paragraph 7

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt maturing within the next twelve months following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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Amount of long-term debt maturing in year five following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year four following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year three following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year two following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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Debt (Details) (USD $)	3 Months Ended		9 Months Ended
Debt (Details) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Jul. 28, 2011 Credit facility	Jul. 28, 2011 Senior revolving credit facility due July 2016
Debt
Maximum borrowing capacity on term loans					$ 800,000,000	$ 250,000,000
Term loan principal payments
2012						2,500,000
2013						7,500,000
2014						12,500,000
2015						17,500,000
2016						210,000,000
Interest income, expense and Other financing costs
Interest income	165,000	223,000	391,000	572,000
Interest expense and other financing costs, net	(4,956,000)	(1,212,000)	(12,005,000)	(3,042,000)
Total interest income, expense and other financing costs	$ (4,791,000)	$ (989,000)	$ (11,614,000)	$ (2,470,000)