Share-based Compensation Arrangement by Share-based Payment Award, Grant Date

No definition available.

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Namespace Prefix:	tgc_
Data Type:	xbrli:dateItemType
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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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

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Period Type:	duration

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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Period Type:	duration

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_AwardTypeAxis=tgc_NonExecutiveDirectorMember
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Data Type:	na
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- Details

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Stock And Stock Options (Schedule Of Options Issued) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Issued	2,500	10,000	10,000
Exercise Price	$ 4.70	$ 6.10	$ 5.70	$ 5.90
$1.20 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price	$ 1.20
Grant Date	Jan. 04, 2016
Expiration Date	Jan. 03, 2021
$1.20 [Member] \| Non-Executive Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Issued	625
$1.20 [Member] \| Four Non-Executive Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Issued	2,500