Subsequent Event (Details) (USD $) In Thousands | Sep. 30, 2011 | Oct. 03, 2011
Empower Research, LLC [Member] |
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| Subsequent Event [Line Items] | ||
| Amount recorded as reserve for doubtful receivable | $ 3,869 | |
| Cash consideration | $ 17,100 |
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- Definition Amount of the reserve created for receivables doubtful of collection from a customer who has filed for the bankruptcy protection after the balance sheet date.
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- Definition Amount of cash paid to acquire the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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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