Intangible Assets - Schedule of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Indefinite-lived Intangible Assets [Line Items]
Beginning Balance	$ 16,733	$ 6,507
Net foreign currency translation	(80)	67
Amortization expense	(4,532)us-gaap_AmortizationOfIntangibleAssets	(3,325)us-gaap_AmortizationOfIntangibleAssets	(1,905)us-gaap_AmortizationOfIntangibleAssets
Ending Balance	12,819	16,733	6,507
End of year, balance at cost	32,518
Accumulated amortization	(19,699)
Ending Balance	12,819	16,733	6,507
Cronto [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions		13,257
Other Acquisitions [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions	698	227
Capitalized Technology [Member]
Indefinite-lived Intangible Assets [Line Items]
Beginning Balance	13,776	4,847
Net foreign currency translation	(38)	6
Amortization expense	(4,053)	(3,014)
Ending Balance	10,216	13,776
End of year, balance at cost	28,947
Accumulated amortization	(18,731)
Ending Balance	10,216	13,776
Capitalized Technology [Member] \| Cronto [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions		11,937
Capitalized Technology [Member] \| Other Acquisitions [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions	531	0
Patents and Trademarks [Member]
Indefinite-lived Intangible Assets [Line Items]
Beginning Balance	1,961	1,642
Net foreign currency translation	(1)	0
Amortization expense	(198)	(143)
Ending Balance	1,929	1,961
End of year, balance at cost	2,435
Accumulated amortization	(506)
Ending Balance	1,929	1,961
Patents and Trademarks [Member] \| Cronto [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions		235
Patents and Trademarks [Member] \| Other Acquisitions [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions	167	227
Other [Member]
Indefinite-lived Intangible Assets [Line Items]
Beginning Balance	996	18
Net foreign currency translation	(41)	61
Amortization expense	(281)	(168)
Ending Balance	674	996
End of year, balance at cost	1,136
Accumulated amortization	(462)
Ending Balance	674	996
Other [Member] \| Cronto [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions		1,085
Other [Member] \| Other Acquisitions [Member]
Indefinite-lived Intangible Assets [Line Items]
Additions	$ 0	$ 0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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