XML 13 R25.htm IDEA: XBRL DOCUMENT v2.4.1.9
Description Of Business And Significant Accounting Policies (Narrative) (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Dec. 31, 2012
Description Of Business And Significant Accounting Policies [Line Items]        
material natural gas imbalances $ 0tgc_RevenueRecognitionNaturalGasImbalances   $ 0tgc_RevenueRecognitionNaturalGasImbalances  
Methane gas revenue 0us-gaap_OtherSalesRevenueNet 0us-gaap_OtherSalesRevenueNet    
Restricted cash 386,000us-gaap_RestrictedCashAndCashEquivalentsNoncurrent   386,000us-gaap_RestrictedCashAndCashEquivalentsNoncurrent  
Unevaluated properties 507,000tgc_OilAndGasPropertyFullCostMethodUnevaluatedProperties   462,000tgc_OilAndGasPropertyFullCostMethodUnevaluatedProperties  
Collateralized Bond [Member]        
Description Of Business And Significant Accounting Policies [Line Items]        
Restricted cash       $ 386,000us-gaap_RestrictedCashAndCashEquivalentsNoncurrent
/ us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis
= tgc_CollateralizedBondMember