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Amount of the second milestone payment due for additional consideration receivable upon achievement of additional development and regulatory milestones under collaborative arrangement.

No definition available.

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Amount of additional consideration receivable upon achievement of certain development and regulatory milestones under collaborative arrangement.

No definition available.

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Amount of aggregate consideration receivable under collaborative arrangement.

No definition available.

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Amount of consideration receivable upon achievement of specified technical requirement.

No definition available.

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Represents the number of milestone payments receivable upon achievement of specified requirements under collaborative arrangement.

No definition available.

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Number of units under arrangement.

No definition available.

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Upfront payment amount received upon entry into collaborative arrangement.

No definition available.

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Represents the number of additional bacteria species added to the existing product candidate.

No definition available.

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Represents the period after the current fiscal year that the entity expects to record revenue, provided development and regulatory milestones are achieved.

No definition available.

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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.

No definition available.

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Cash received from collaborators during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

No definition available.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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

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Name:	us-gaap_CounterpartyNameAxis=ttoo_CanonU.S.LifeSciencesIncMember
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Name:	us-gaap_TypeOfArrangementAxis=ttoo_CoDevelopmentPartnershipAgreementMember
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