Equity Offering Costs

No definition available.

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- Definition

Special Dividend ESOP Charges

+ References

No definition available.

+ Details

Name:	gff_SpecialDividendESOPCharges
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The loss recognized on termination of a contract.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 275
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84167019&loc=d3e54681-109401

+ Details

Name:	us-gaap_LossOnContractTermination
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow for proceeds from settlement of corporate-owned life insurance policy, classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21C
-URI http://asc.fasb.org/extlink&oid=109223946&loc=SL94080552-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

Name:	us-gaap_ProceedsFromLifeInsurancePolicies
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) - USD ($)	3 Months Ended			12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Quarterly Financial Information Disclosure [Abstract]
Acquisition related costs	$ 2,320,000	$ 378,000	$ 2,348,000		$ 6,145,000
Proceeds from life insurance policy			$ 248
Special dividend ESOP charges	2,125,000
Equity offering costs	$ 795			$ 1,205,000	0	$ 0
Contract settlement charges					$ 3,300,000