Financial Instruments (Unobservable inputs) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	May 31, 2012	May 31, 2012	May 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Number of communities assessed for impairment	13
Discount rate for impairment		20.00%
Active communities	438	438	449
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Average selling price	310,000
Absorption rate per quarter (homes)	13
Discount rate for impairment	20.00%
Capitalization rate		13.00%
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Average selling price	83,000
Absorption rate per quarter (homes)	1
Discount rate for impairment	20.00%
Capitalization rate		6.00%