Other Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Other Assets
Collateral deposits	$ 5,165	$ 5,165
Prepaid expenses	4,424	2,761
Other	419	1,104
Total other assets	$ 10,008	$ 9,030

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

+ References

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

-Publisher FASB

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- Definition

The sum of the carrying amounts, as of the balance sheet date, of assets which have not been itemized or categorized in the footnotes to the financial statements and are a component of Other Assets (OtherAssets).

+ References

No definition available.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

+ References

+ Details

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