XML 49 R51.htm IDEA: XBRL DOCUMENT v2.4.0.8

Stock-Based Compensation - Option Activity under the Stock-Based Compensation Plan (Detail) (USD $)	Sep. 30, 2013	Sep. 30, 2012	May 28, 2012	Sep. 30, 2011
Option 2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Options granted			20,000
Number of Shares, Options outstanding	318,000	318,000		298,000
Average Exercise Price Per Share, Options granted			$ 7.150
Average Exercise Price Per Share, Options outstanding	$ 7.655	$ 7.655		$ 7.689
Option 1997 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Options outstanding	27,500	27,500		27,500
Average Exercise Price Per Share, Options outstanding	$ 9.32	$ 9.32		$ 9.32

X

- Definition

Share based compensation arrangement by share based payment award options granted.

+ References

No definition available.

+ Details

Name:	genc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGranted
Namespace Prefix:	genc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Share based compensation arrangements by share based payment award options grants weighted average exercise price.

+ References

No definition available.

+ Details

Name:	genc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsWeightedAverageExercisePrice
Namespace Prefix:	genc_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901



Reference 2: 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)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- 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

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