XML 47 R56.htm IDEA: XBRL DOCUMENT v2.4.1.9
Derivative and Hedging Financial Instruments - Additional Information (Detail) (USD $)
 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 0 Months Ended
Jul. 31, 2014
MMBTU
Jun. 30, 2013
MMBTU
Dec. 31, 2014
MMBTU
Dec. 31, 2014
MMBTU
Nov. 30, 2018
MMBTU
Apr. 30, 2015
MMBTU
Oct. 31, 2018
MMBTU
Jan. 31, 2015
MMBTU
Dec. 20, 2013
Dec. 23, 2014
Aug. 20, 2014
May 21, 2013
May 09, 2013
Dec. 31, 2013
May 21, 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Costless collars covering percentage on its expected natural gas production                         85.00%teng_PercentageOfExpectedNaturalGasProductionCoveredByDerivativeCollars    
Total MMBtu hedged over the period     3.4teng_EnergyVolumeHedgedDuringPeriod                        
Monthly volumes declining of MMBtu 444,534teng_MonthlyEnergyVolumeHedged 207,000teng_MonthlyEnergyVolumeHedged                          
Fixed price covering percentage on its expected natural gas production                   50.00%teng_PercentageOfExpectedNaturalGasProductionCoveredByFixedPriceHedges 90.00%teng_PercentageOfExpectedNaturalGasProductionCoveredByFixedPriceHedges 90.00%teng_PercentageOfExpectedNaturalGasProductionCoveredByFixedPriceHedges      
Warrant expiry date     Feb. 28, 2015                        
Maximum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Monthly volumes declining of MMBtu       266,891teng_MonthlyEnergyVolumeHedged
/ us-gaap_RangeAxis
= us-gaap_MaximumMember		                      
Scenario, Forecast [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Monthly volumes declining of MMBtu         171,940teng_MonthlyEnergyVolumeHedged
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember		 113,000teng_MonthlyEnergyVolumeHedged
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember		                  
Scenario, Forecast [Member] | Minimum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Monthly volumes declining of MMBtu             33,200teng_MonthlyEnergyVolumeHedged
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember		                
Morgan Stanley Fixed I [Member] | July 2014 to November 2018 [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Total MMBtu hedged over the period     13,932,171teng_EnergyVolumeHedgedDuringPeriod
/ us-gaap_EnergyAxis
= teng_GasHedgesOneMember
/ us-gaap_StatementScenarioAxis
= teng_JulyTwoThousandAndFourteenToNovemberTwoThousandAndEighteenMember		                        
Morgan Stanley Fixed II [Member] | January 2015 To November 2014 [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Total MMBtu hedged over the period     10,499,038teng_EnergyVolumeHedgedDuringPeriod
/ us-gaap_EnergyAxis
= teng_GasHedgesTwoMember
/ us-gaap_StatementScenarioAxis
= teng_NovemberTwoThousandAndFourteenToJanuaryTwoThousandAndFifteenMember		                        
Morgan Stanley Fixed III [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Total MMBtu hedged over the period     7,301,209teng_EnergyVolumeHedgedDuringPeriod
/ us-gaap_EnergyAxis
= teng_GasHedgesThreeMember		                        
Morgan Stanley Fixed III [Member] | Scenario, Forecast [Member] | Minimum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Monthly volumes declining of MMBtu             104,084teng_MonthlyEnergyVolumeHedged
/ us-gaap_EnergyAxis
= teng_GasHedgesThreeMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember		                
Energy Related Derivative [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Fair value of commodity contracts     410,389us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_EnergyRelatedDerivativeMember		 410,389us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_EnergyRelatedDerivativeMember		                   $ (125,773)us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_EnergyRelatedDerivativeMember		  
Price Risk Derivative [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Fair value of commodity contracts                   (716,488)us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_PriceRiskDerivativeMember		          
Price Risk Derivative [Member] | July 2014 to November 2018 [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Fair value of commodity contracts     5,878,302us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_PriceRiskDerivativeMember
/ us-gaap_StatementScenarioAxis
= teng_JulyTwoThousandAndFourteenToNovemberTwoThousandAndEighteenMember		 5,878,302us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_PriceRiskDerivativeMember
/ us-gaap_StatementScenarioAxis
= teng_JulyTwoThousandAndFourteenToNovemberTwoThousandAndEighteenMember		                      
Price Risk Derivative [Member] | January 2015 To November 2014 [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Fair value of commodity contracts     1,941,465us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_PriceRiskDerivativeMember
/ us-gaap_StatementScenarioAxis
= teng_NovemberTwoThousandAndFourteenToJanuaryTwoThousandAndFifteenMember		 1,941,465us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_PriceRiskDerivativeMember
/ us-gaap_StatementScenarioAxis
= teng_NovemberTwoThousandAndFourteenToJanuaryTwoThousandAndFifteenMember		                      
Put Option [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Strike Price of Costless Collar                         4.00us-gaap_DerivativePriceRiskOptionStrikePrice
/ us-gaap_OptionIndexedToIssuersEquityEquityAxis
= us-gaap_PutOptionMember		    
Call Option [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Strike Price of Costless Collar                         4.28us-gaap_DerivativePriceRiskOptionStrikePrice
/ us-gaap_OptionIndexedToIssuersEquityEquityAxis
= us-gaap_CallOptionMember		    
Subsequent Event [Member] | Maximum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Monthly volumes declining of MMBtu               326,700teng_MonthlyEnergyVolumeHedged
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember		              
ASD Credit Agreement [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Warrants and rights outstanding     2,000,000us-gaap_WarrantsAndRightsOutstanding
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		 2,000,000us-gaap_WarrantsAndRightsOutstanding
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		                      
Warrants Rights     19,500us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		 19,500us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		                      
ASD Stock Percentage     19.50%teng_PercentageOfWarrantsRepresentStock
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		                        
Warrants exercise price     263.44invest_InvestmentWarrantsExercisePrice
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		                        
Repurchase of warrants                 $ 9,000,000us-gaap_PaymentsForRepurchaseOfWarrants
/ us-gaap_LineOfCreditFacilityAxis
= teng_AmericanShaleDevelopmentCreditMember		            
Swap [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Strike Price of Costless Collar                     3.92us-gaap_DerivativePriceRiskOptionStrikePrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember		        
Strike Price of fixed price hedges                   (1.12)us-gaap_DerivativeSwapTypeFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember		          
Swap [Member] | Maximum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Strike Price of Costless Collar                             4.38us-gaap_DerivativePriceRiskOptionStrikePrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Swap [Member] | Minimum [Member]                              
Derivative Instruments and Hedging Activities Disclosures [Line Items]                              
Strike Price of Costless Collar                             4.06us-gaap_DerivativePriceRiskOptionStrikePrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember