Acquisition - Preliminary Purchase Price Allocation (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended	1 Months Ended
Dec. 31, 2013	Feb. 28, 2013
Disclosure - Acquisition - Preliminary Purchase Price Allocation (Detail) [Line Items]
Purchase price, net of acquired cash	$ 37,827
Intangible assets		13,255
Xtrakter Limited [Member]
Disclosure - Acquisition - Preliminary Purchase Price Allocation (Detail) [Line Items]
Purchase price		46,683
Less: acquired cash		(8,856)
Purchase price, net of acquired cash		37,827
Accounts receivable		3,733
Intangible assets		13,255
Other assets		1,718
Deferred tax liability, net		(2,342)
Accounts payable, accrued expenses and deferred revenue		(4,622)
Goodwill		$ 26,085

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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