Revenue to External Customers Based on Billing Location of End User Customer and Long-Lived Assets by Geography (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenue:
Revenue from United States	$ 94,866	$ 73,010	$ 48,059
International revenue	31,125	25,929	16,860
Total revenue	125,991	98,939	64,919
Long-lived assets:
Long-lived assets in United States	37,869	28,831
International long-lived assets	7,447	5,418
Property and equipment, net	$ 45,316	$ 34,249

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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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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