Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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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 of liability recognized arising from contingent consideration in a business combination.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

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Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

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Business combination contingent additional consideration transferred.

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Acquisition of Cronto - Additional Information (Detail) (Cronto [Member]) In Thousands, unless otherwise specified	0 Months Ended		1 Months Ended		12 Months Ended			12 Months Ended
	May 20, 2013 USD ($)	May 20, 2013 EUR (€)	Jun. 30, 2013 USD ($)	Jun. 30, 2013 GBP (£)	Dec. 31, 2014 USD ($)	Dec. 31, 2014 EUR (€)	May 20, 2013	Dec. 31, 2014 Minimum [Member]	Dec. 31, 2014 Maximum [Member]
Business Acquisition [Line Items]
Percentage of stock acquired by the Company							100.00%
Initial consideration	$ 19,611	€ 15,000
Exchange rate			1.55	1.55			1.31
Additional consideration			555	358
Contingent consideration					2,620	2,000
Acquired identifiable intangible assets					$ 13,257
Estimated useful lives of asset								2 years	5 years