Goodwill and Other Intangible Assets - Carrying Value of Goodwill and Other Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 61,680	$ 3,874
Identified intangibles, net	2,188	1,577
Total	$ 63,868	$ 5,451

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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