Represents the additional cash inflow associated with the sale of cash method investments.

No definition available.

Name:	grif_AdditionalProceedsFromSaleOfCostMethodInvestments
Namespace Prefix:	grif_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the cost method of accounting.

+ References

No definition available.

+ Details

Name:	grif_CostMethodInvestmentOwnershipPercentage
Namespace Prefix:	grif_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow associated with sale of cost method investments.

+ References

No definition available.

+ Details

Name:	grif_ProceedsFromSaleOfCostMethodInvestments
Namespace Prefix:	grif_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the total cash inflow associated with the sale of cash method investments.

+ References

No definition available.

+ Details

Name:	grif_TotalProceedsFromSaleOfCostMethodInvestments
Namespace Prefix:	grif_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph c, d

-Article 5

+ Details

Name:	us-gaap_CostMethodInvestmentsRealizedGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
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Investments (Details 2) (USD $) In Thousands, unless otherwise specified	0 Months Ended	3 Months Ended
	Jan. 18, 2013	Mar. 02, 2013	Dec. 01, 2012
Investments
Gain on sale of investment		$ 3,397
Cash proceeds received at closing		3,226
SNHC
Investments
Equity interest in cost method investment (as a percent)			14.00%
Total cash proceeds from sale of investment	3,418
Gain on sale of investment	3,397
Cash proceeds received at closing		3,226
SNHC \| Subsequent events
Investments
Additional cash proceeds received subsequent to closing		$ 192