Annual report pursuant to Section 13 and 15(d)

Income Taxes (Details 2)

v2.4.1.9
Income Taxes (Details 2) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Percent of pre-tax income:      
U.S. federal statutory income tax rate (as a percent) 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate  
Permanent Differences (as a percent) (0.60%)us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpense (0.50%)us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpense  
State taxes, net of federal benefit (as a percent) 6.50%us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes 6.50%us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes  
Research and development credit (as a percent) 3.90%us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseResearchAndDevelopment 1.90%us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseResearchAndDevelopment  
Change in valuation allowance (as a percent) (43.80%)us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance (41.90%)us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance  
Effective income tax rate (as a percent) 0.00%us-gaap_EffectiveIncomeTaxRateContinuingOperations 0.00%us-gaap_EffectiveIncomeTaxRateContinuingOperations  
Operating loss carryforwards      
Interest and penalties related to uncertain tax positions $ 0us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued    
Research and development credit retroactively reinstated 1,800,000trvn_DeferredTaxAssetsReinstatedTaxCreditCarryforwardsResearch 1,000,000trvn_DeferredTaxAssetsReinstatedTaxCreditCarryforwardsResearch 1,000,000trvn_DeferredTaxAssetsReinstatedTaxCreditCarryforwardsResearch
Research and development.      
Operating loss carryforwards      
Uncertain tax positions 0trvn_LiabilityForUncertainTaxPositions
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_ResearchMember
   
U.S. federal      
Operating loss carryforwards      
Net operating loss carryforwards 22,800,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
12,700,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
 
U.S. federal | Research and development.      
Operating loss carryforwards      
Tax credit carryforwards 4,700,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_ResearchMember
2,500,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_ResearchMember
 
U.S. State      
Operating loss carryforwards      
Net operating loss carryforwards 22,800,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
12,700,000us-gaap_OperatingLossCarryforwards
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
 
U.S. State | Research and development.      
Operating loss carryforwards      
Tax credit carryforwards $ 700,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_ResearchMember
$ 400,000us-gaap_TaxCreditCarryforwardAmount
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_StateAndLocalJurisdictionMember
/ us-gaap_TaxCreditCarryforwardAxis
= us-gaap_ResearchMember