Inventory Impairments and Land Option Contract Abandonments (Details) (USD $)	3 Months Ended	9 Months Ended	12 Months Ended
Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2011	Aug. 31, 2010	Nov. 30, 2010	Aug. 15, 2011
Inventory Impairments and Land Option Contract Abandonments (Textuals)
Number of land parcels or communities evaluated for recoverability	33	33	97	88
Discount rate used in estimating discounted cash flow	17.00%	18.00%	17.00%	20.00%
Pretax, noncash inventory impairment charges	$ 328,000	$ 1,434,000	$ 21,414,000	$ 8,269,000	$ 9,800,000
Number of land parcels or communities associated with non cash inventory impairment charges	1	1	9	5
Post impairment fair value of land parcels or communities	1,100,000	2,700,000	29,900,000	6,600,000
Land option contract abandonment charges	834,000	1,943,000	2,093,000	8,470,000
Number of Lots on which abandonment charges are recognized	209	284	467	685
Aggregate carrying value of inventory impacted by pretax, noncash inventory impairment charges	366,800,000		366,800,000		418,500,000
Number of communities and various other land parcels impacted by pretax, noncash inventory impairment charges	56		56		72
Charges related to adjustment to the fair value of real estate			18,100,000
Range of Remaining Estimated Inventory Operating Life			From One year to in excess of 10 years
Expected Realization Period of Inventory Minimum	3		3
Expected Realization Period of Inventory Maximum	5		5
Repayment of aggregate principal amount of senior notes						100,000,000
Senior notes						$ 100,000,000
Senior notes, rate						6.375%

Aggregate carrying value of inventory impacted by pretax, noncash inventory impairment charges.

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Charges related to Adjustment to the fair value of real estate.

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Discount rate used in estimating discounted cash flow.

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Expected Realization Period of Inventory Maximum.

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Expected Realization Period of Inventory Minimum.

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Inventory Impairments and Land Option Contract Abandonments.

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Land option contract abandonment charges.

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Number of communities and various other land parcels impacted by pretax, noncash inventory impairment charges.

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Number Of Land Parcels Or Communities Associated With Non Cash Inventory Impairment Charges.

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Number of land parcels or communities evaluated for recoverability.

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Number of Lots on which abandonment charges are recognized.

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Post impairment fair value of land parcels or communities.

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Range of Remaining Estimated Inventory Operating Life.

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Repayment of aggregate principal amount of senior notes.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

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