XML 24 R67.htm IDEA: XBRL DOCUMENT
v3.20.1

Supplemental Oil And Gas Information (Schedule Of Reserve Value By Category And The Respective Present Values, Before Income Taxes, Discounted At 10% As A Percentage Of Total Proved Reserves) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report | $ 8,365 | $ 13,976 | $ 8,170
Proved developed producing reserves (PDP) | $ 7,592 | $ 12,534 | $ 7,065
% of PDP reserves to total proved reserves | 91.00% | 90.00% | 87.00%
Proved developed non-producing reserves | $ 773 | $ 739 | $ 1,082
% of PDNP reserves to total proved reserves | 9.00% | 5.00% | 13.00%
Proved undeveloped reserves (PUD) |  | $ 703 | $ 23
% of PUD reserves to total proved reserves |  | 5.00% |
Oil [Member] |  |  |
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report | $ 8,365 | $ 13,976 | 8,170
Proved developed producing reserves (PDP) | $ 7,592 | $ 12,534 | $ 7,065
% of PDP reserves to total proved reserves | 91.00% | 90.00% | 87.00%
Proved developed non-producing reserves | $ 773 | $ 739 | $ 1,082
% of PDNP reserves to total proved reserves | 9.00% | 5.00% | 13.00%
Proved undeveloped reserves (PUD) |  | $ 703 | $ 23
% of PUD reserves to total proved reserves |  | 5.00% |
Gas [Member] |  |  |
Reserve Quantities [Line Items] |  |  |
Total proved reserves year-end reserve report |  |  |
Proved developed producing reserves (PDP) |  |  |
% of PDP reserves to total proved reserves |  |  |
Proved developed non-producing reserves |  |  |
% of PDNP reserves to total proved reserves |  |  |
Proved undeveloped reserves (PUD) |  |  |
% of PUD reserves to total proved reserves |  |  |

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | srt_ReserveQuantitiesLineItems
Namespace Prefix: | srt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Proved Developed Non-Producing Reserves To Total Proved Reserves + References No definition available. + Details
Name: | tgc_PercentOfProvedDevelopedNonProducingReservesToTotalProvedReserves
Namespace Prefix: | tgc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Proved Developed Producing Reserves To Total Proved Reserves + References No definition available. + Details
Name: | tgc_PercentOfProvedDevelopedProducingReservesToTotalProvedReserves
Namespace Prefix: | tgc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Proved Undeveloped Reserves To Total Proved Reserves + References No definition available. + Details
Name: | tgc_PercentOfProvedUndevelopedReservesToTotalProvedReserves
Namespace Prefix: | tgc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Proved Developed Non-Producing Reserves + References No definition available. + Details
Name: | tgc_ProvedDevelopedNonProducingReserves
Namespace Prefix: | tgc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Proved Developed Producing Reserves + References No definition available. + Details
Name: | tgc_ProvedDevelopedProducingReserves
Namespace Prefix: | tgc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Proved Reserves + References No definition available. + Details
Name: | tgc_ProvedReserves
Namespace Prefix: | tgc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Proved Undeveloped Reserves + References No definition available. + Details
Name: | tgc_ProvedUndevelopedReserves
Namespace Prefix: | tgc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_OilReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_NaturalGasReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |