DISCONTINUED OPERATIONS (Detail) - Summary of discontinued operations (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Sep. 30, 2012
Assets of discontinued operations:
Prepaid and other current assets	$ 556	$ 587
Other long-term assets	2,665	2,936
Total assets of discontinued operations	3,221	3,523
Liabilities of discontinued operations:
Accrued liabilities, current	1,954	3,639
Other long-term liabilities	3,110	3,643
Total liabilities of discontinued operations	$ 5,064	$ 7,282

Name:	gff_AssetsOfDiscontinuedOperationsAbstract
Namespace Prefix:	gff_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for noncurrent and current assets to be sold or that has subsequently been disposed of through sale, as of the financial statement date.

+ References

No definition available.

+ Details

Name:	gff_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrentAndNoncurrent
Namespace Prefix:	gff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	gff_LiabilitiesOfDiscontinuedOperationsAbstract
Namespace Prefix:	gff_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of current and non-current obligations arising from the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

+ References

No definition available.

+ Details

Name:	gff_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrentAndNoncurrent
Namespace Prefix:	gff_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred and payable pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include interest, rent, salaries, and utilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 47

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount as of the balance sheet date of assets not otherwise specified, and which are expected to be realized or consumed after one year or beyond the normal operating cycle, if longer. For an unclassified balance sheet, represents both current and noncurrent other assets.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), obligations not otherwise itemized that are due after one year or operating cycle, if longer, from the balance sheet date.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant