Annual report pursuant to Section 13 and 15(d)

Nature of business and operations (Details)

v2.4.1.9
Nature of business and operations (Details)
12 Months Ended
Dec. 31, 2014
segment
Sale of Stock By Subsidiary [Line Items]  
Number of Operating Segments 1us-gaap_NumberOfOperatingSegments
Ilios  
Sale of Stock By Subsidiary [Line Items]  
The Company's ownership percentage in subsidiary 65.00%us-gaap_MinorityInterestOwnershipPercentageByParent
/ dei_LegalEntityAxis
= tcgn_IliosMember
Restricted stock | Ilios  
Sale of Stock By Subsidiary [Line Items]  
The Company's ownership percentage in subsidiary 63.70%us-gaap_MinorityInterestOwnershipPercentageByParent
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
/ dei_LegalEntityAxis
= tcgn_IliosMember