Segment Information - Summary of Revenue, Property and Equipment, Net by Geographic Region (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net revenues:
United States	$ 230,336	$ 244,897	$ 209,583
International	300,128	304,435	213,761
Total net revenues	530,464	549,332	423,344
Property and equipment, net:
United States	30,477	32,925
International	7,645	7,544
Property and equipment, net	$ 38,122	$ 40,469

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Amount of long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets, located in the entity's country of domicile.

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Revenues from external customers attributed to the entity's country of domicile.

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Revenues from external customers attributed to all foreign countries in total from which the entity derives revenues.

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Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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