Commitments And Contingencies (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Loss Contingencies [Line Items]
Production costs and taxes	$ 1,202,000tgc_ProductionCostsAndTaxes	$ 1,399,000tgc_ProductionCostsAndTaxes
Decrease in compensation	(23,000)
Incidence Of Non-Compliance [Member]
Loss Contingencies [Line Items]
Wells issued incidence of non-compliance	1
Maximum potential loss	386,000
Production costs and taxes	$ 386,000
Minimum [Member]
Loss Contingencies [Line Items]
Compensation reduction until WTI posting	70
Compensation reimbursement at WTI posting	85

Compensation Reduction Until, Thirty Day Trailing Average Of West Texas Intermediate

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Compensation Reimbursement At Thirty Day Trailing Average Of West Texas Intermediate

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- Definition

Increase (Decrease) Labor and Related Expense

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- Definition

Number Of Wells Under Bureau Of Ocean Energy Management Non-Compliance

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- Definition

Cost incurred related to the upstream oil and gas activities, such as the exploration, development, and production of crude petroleum and natural gas and all taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax.

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The estimated maximum amount of possible loss from the contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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