Organization and Basis of Presentation - Property and equipment (Details)	6 Months Ended
Jun. 30, 2018
Property and Equipment
Finite-Lived Intangible Asset, Useful Life	10 years
Machinery and laboratory equipment \| Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	3 years
Machinery and laboratory equipment \| Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	5 years
Instruments \| Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	4 years
Instruments \| Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	5 years
Office equipment \| Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	3 years
Office equipment \| Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	7 years
Leasehold improvements
Property and Equipment
Property, Plant and Equipment, Estimated Useful Lives	over the shorter of the remaining life of the lease or the useful economic life of the asset

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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- Definition

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68071081&loc=d3e1205-110223

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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