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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The expense recognized in the current period that allocates the cost of a tangible asset over the asset's useful life. This element applies only to an asset used in the production of goods sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a))
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- References

No definition available.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 13
-Subparagraph a
-Article 5

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 8
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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.

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Supplemental Balance Sheet Information - Property and Equipment - (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Property and Equipment
Property and equipment, gross	$ 22,196		$ 20,655
Accumulated depreciation and amortization	(7,728)		(7,066)
Property and equipment, net	14,468		13,589
Office and computer equipment
Property and Equipment
Property and equipment, gross	409		409
Software
Property and Equipment
Property and equipment, gross	743		708
Laboratory equipment
Property and Equipment
Property and equipment, gross	4,562		4,516
Furniture
Property and Equipment
Property and equipment, gross	200		200
Manufacturing equipment
Property and Equipment
Property and equipment, gross	910		897
Manufacturing tooling and molds
Property and Equipment
Property and equipment, gross	154		154
T2-owned instruments and components
Property and Equipment
Property and equipment, gross	10,522		9,119
Leasehold improvements
Property and Equipment
Property and equipment, gross	3,353		3,353
Construction in progress
Property and Equipment
Property and equipment, gross	1,343		1,299
T2 Owned Instruments in Service
Property and Equipment
Property and equipment, gross	$ 6,700		$ 5,700
Estimated useful lives (in years)	5 years
Depreciation expense recorded as a component of cost of product revenue	$ 200	$ 100