Quarterly report pursuant to Section 13 or 15(d)

Related party transactions (Details)

v2.4.1.9
Related party transactions (Details) (USD $)
3 Months Ended 12 Months Ended 3 Months Ended 12 Months Ended
Mar. 31, 2015
company
Mar. 31, 2014
Dec. 31, 2012
Dec. 31, 2013
Dec. 31, 2013
Dec. 31, 2014
Related Party Transaction [Line Items]            
Number of affiliated companies 2tcgn_RelatedPartyTransactionNumberOfAffiliatedCompanies          
Interest Paid $ 30,059us-gaap_InterestPaid $ 233,220us-gaap_InterestPaid        
Convertible debentures | Common stock            
Related Party Transaction [Line Items]            
Common stock issuable upon conversion     555,556us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonStockMember
     
Michaelson Capital Special Finance Fund LP. [Member] | Convertible debentures            
Related Party Transaction [Line Items]            
Related party debt, stated interest rate       4.00%us-gaap_RelatedPartyTransactionRate
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
   
Debt Instrument, Term       3 years    
Conversion price in usd per share           $ 5.40us-gaap_DebtInstrumentConvertibleConversionPrice1
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
Debt Issuance Cost       147,577us-gaap_DebtIssuanceCosts
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
   
Debt conversion, amount converted       1,000us-gaap_DebtConversionOriginalDebtAmount1
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
   
Current portion of convertible debentures, related party           $ 3,000,000tcgn_ConvertibleDebentureRelatedPartiesCurrent
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
Michaelson Capital Special Finance Fund LP. [Member] | Convertible debentures | Common stock            
Related Party Transaction [Line Items]            
Debt conversion, number of shares issued       185.19us-gaap_DebtConversionConvertedInstrumentSharesIssued1
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonStockMember
   
Common stock issuable upon conversion         555,556us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments
/ us-gaap_LongtermDebtTypeAxis
= tcgn_ConvertibleUnsecuredDebtMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= tcgn_MichaelsonCapitalSpecialFinanceFundLP.Member
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonStockMember