Commitments and Contingencies (Details Textual) (USD $)	3 Months Ended		9 Months Ended
	Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2011	Aug. 31, 2010	May 31, 2011	Nov. 30, 2010	May 31, 2010	Nov. 30, 2009
Commitments And Contingencies (Textuals) [Abstract]
Structural warranty provided by the company			10 years
Maximum warranty on electrical and other building systems			5 years
Minimum warranty on electrical and other building systems			2 years
Warranty for other components of a home			1 year
Net warranty adjustments	$ (7,374,000)	$ 352,000	$ (6,242,000)	$ (2,329,000)
Company's warranty liability	70,499,000	101,930,000	70,499,000	101,930,000	82,630,000	93,988,000	117,753,000	135,749,000
Warranty liability associated with defective drywall	5,900,000		5,900,000			11,300,000
Number of homes containing or suspected of containing defective drywall	112		112			296
Number of affected homes on which repairs were resolved	211		211
Accumulated Number of affected homes on which repairs were resolved	352		352
Additional Number of affected homes associated with repair costs			27
Accumulated number of homes identified affected associated with overall warranty liability			464
Payments made for the repair of homes containing defective drywall			11,800,000	19,400,000
Estimated additional charges for homes containing defective drywall			6,300,000	19,500,000
Payments made as repair costs for homes containing defective drywall			38,600,000
Estimated Repair Costs For Homes Containing Defective Drywall			44,500,000
Number of lawsuits in which company is a defendant	10		10
Company's estimated liabilities for construction defect	95,700,000		95,700,000			95,700,000
Expenses associated with self-insurance	2,100,000	1,600,000	6,700,000	5,200,000
Performance bonds	392,400,000		392,400,000			414,300,000
Letters of Credit Outstanding, Amount	64,300,000		64,300,000			87,500,000
Non-Refundable Cash Deposits on Land Option and Other Similar Contracts	15,600,000		15,600,000			14,800,000
Letters of credit	2,000,000		2,000,000			4,200,000
Total deposits	17,600,000		17,600,000
Aggregate purchase price of land	$ 329,800,000		$ 329,800,000