Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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

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-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property and Equipment
Property and equipment, gross	$ 1,183us-gaap_PropertyPlantAndEquipmentGross	$ 769us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation and amortization	403	688
Property and equipment, net	780us-gaap_PropertyPlantAndEquipmentNet	81us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	160us-gaap_Depreciation	71us-gaap_Depreciation	139us-gaap_Depreciation
Lab equipment
Property and Equipment
Property and equipment, gross	519	511
Computer equipment
Property and Equipment
Property and equipment, gross	110	100
Software
Property and Equipment
Property and equipment, gross	74	119
Furniture and fixtures
Property and Equipment
Property and equipment, gross	320	11
Leasehold improvements
Property and Equipment
Property and equipment, gross	158	21
Assets in Progress
Property and Equipment
Property and equipment, gross	$ 2	$ 7