Identified Intangible Assets and Goodwill (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Changes in the carrying amount of goodwill
Balance as of December 31, 2010	$ 188,698
Exit of the ESG business	(116,321)
Balance as of December 31, 2011	$ 72,377

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details