v2.3.0.15

Subsequent Event	9 Months Ended
	Sep. 30, 2011
Subsequent Event [Abstract]
Subsequent Event	23. Subsequent event Subsequent to September 30, 2011, one of the clients of the Company filed for bankruptcy protection in the US Bankruptcy Court. Accordingly, the Company has recorded a reserve for doubtful receivable of $3,869 during the quarter ended September 30, 2011. On October 3, 2011, the Company completed its acquisition of Empower Research, LLC ("Empower") for cash consideration of $17,100, subject to adjustment based on working capital, cash balances, current indebtedness and company expenses. The agreement also provides for an additional deferred consideration and a contingent earn-out consideration. Empower is an integrated media and business research company with strong capabilities in social media research and measurement.

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The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

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