Segment and Geographic Information - Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenue	$ 451,066us-gaap_SalesRevenueGoodsNet	$ 326,786us-gaap_SalesRevenueGoodsNet	$ 295,588us-gaap_SalesRevenueGoodsNet
Service revenue	35,204us-gaap_SalesRevenueServicesNet	27,100us-gaap_SalesRevenueServicesNet	28,691us-gaap_SalesRevenueServicesNet
Long-lived assets	141,831us-gaap_NoncurrentAssets	135,686us-gaap_NoncurrentAssets	134,106us-gaap_NoncurrentAssets
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenue	132,298	103,610	87,877
Service revenue	15,143	13,505	13,248
Long-lived assets	118,991	118,619	120,596
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenue	192,463	104,497	95,376
Service revenue	12,536	6,012	6,083
Long-lived assets	11,385	5,059	4,939
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenue	38,952	33,763	38,151
Service revenue	4,434	4,103	5,043
Long-lived assets	1,551	1,732	2,229
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Product revenue	87,353	84,916	74,184
Service revenue	3,091	3,480	4,317
Long-lived assets	$ 9,904	$ 10,276	$ 6,342

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 41

-Subparagraph (b)

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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