Property and Equipment, Net - Property and Equipment under Capital Leases (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property and equipment	$ 13,000us-gaap_CapitalLeasedAssetsGross	$ 10,507us-gaap_CapitalLeasedAssetsGross
Less accumulated depreciation and amortization	(4,959)	(5,038)
Property and equipment under capital leases, net	8,041	5,469
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	8,729	7,885
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1,250	575
Computer Hardware [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	2,454	1,607
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	523	306
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 44	$ 134

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 2)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

+ Details

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Balance Type:	credit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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