Aggregate Area of undeveloped Land.

No definition available.

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- Definition

Represents the estimated pretax gain on sale that would be recognized after all costs are incurred and total revenue is recognized.

+ References

No definition available.

+ Details

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- Definition

Funds held in escrow for the acquisition of a replacement property, as a part of the Section 1031 like-kind exchange.

+ References

No definition available.

+ Details

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- Definition

Area of land sold.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Represents the percentage of total cost incurred, related to the sale of real estate property.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of real estate depreciation expense for the period.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Represents the percentage of revenue and pretax gain from sale of real estate property recognized based on the percentage of total costs incurred related to sale.

+ References

No definition available.

+ Details

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- Definition

Represents the sale price of land.

+ References

No definition available.

+ Details

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

+ Details

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of interest capitalized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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- Definition

Revenue from the sale of land in the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Useful life on which depreciation was computed for entities with a substantial portion of business acquiring and holding investment real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 970

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-28)

-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule III)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

+ Details

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Period Type:	duration

- Details

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(3))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 7

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- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

+ Details

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- Definition

Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Real Estate Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Nov. 30, 2014	Nov. 30, 2013 acre
Real estate assets
Real estate assets, gross	$ 213,322		$ 209,284
Accumulated depreciation	(75,910)		(74,762)
Real estate assets, net	137,412us-gaap_RealEstateInvestmentPropertyNet		134,522us-gaap_RealEstateInvestmentPropertyNet
Depreciation expense	1,550grif_RealEstateDepreciationExpense	1,424grif_RealEstateDepreciationExpense
Capitalized interest	163us-gaap_InterestCostsCapitalized	124us-gaap_InterestCostsCapitalized
Sales
Deferred revenue that will be recognized as the construction of roadways connecting the land with existing town roads	7,957us-gaap_DeferredRevenue		8,349us-gaap_DeferredRevenue
Held for Sale
Real estate assets
Real estate assets, gross	9,963		9,943
Land
Real estate assets
Real estate assets, gross	17,955		17,955
Land \| Windsor undeveloped land sale
Sales
Number of acres sold				90
Sale price				9,000
Number of acres of undeveloped land				253
Proceeds from land sale deposited in escrow				8,860
Percentage of cost incurred on sale of land	74.00%
Percentage of total revenue and pretax gain on sale have been recognized	74.00%
Revenue from sale of land	826	93	3,105	2,668
Pretax gain on land sale	622	69	2,358	1,990
Deferred revenue that will be recognized as the construction of roadways connecting the land with existing town roads	2,369
Estimated pretax gain on sale that would be recognized after incurring total costs and recognizing total revenue	6,754		6,754	6,754
Land \| Held for Sale
Real estate assets
Real estate assets, gross	286		286
Land improvements
Real estate assets
Real estate assets, gross	18,568		18,527
Land improvements \| Minimum
Real estate assets
Estimated Useful Lives		10 years
Land improvements \| Maximum
Real estate assets
Estimated Useful Lives		30 years
Buildings and improvements
Real estate assets
Real estate assets, gross	137,430		135,857
Buildings and improvements \| Minimum
Real estate assets
Estimated Useful Lives		10 years
Buildings and improvements \| Maximum
Real estate assets
Estimated Useful Lives		40 years
Tenant improvements
Real estate assets
Real estate assets, gross	17,430		14,820
Machinery and equipment
Real estate assets
Real estate assets, gross	11,810		11,810
Machinery and equipment \| Minimum
Real estate assets
Estimated Useful Lives		3 years
Machinery and equipment \| Maximum
Real estate assets
Estimated Useful Lives		20 years
Development costs
Real estate assets
Real estate assets, gross	10,129		10,315
Development costs \| Held for Sale
Real estate assets
Real estate assets, gross	$ 9,677		$ 9,657