Basis of Presentation and Significant Accounting Policies (Narratives) (Details) (USD $)	3 Months Ended		6 Months Ended
	May 31, 2013 Rate	May 31, 2012 Rate	May 31, 2013 Rate	May 31, 2012 Rate	Nov. 30, 2012	Jan. 29, 2013 Convertible senior notes due February 1, 2019 at 1.375%
Debt Instrument [Line Items]
Debt instrument, face amount						$ 230,000,000
Debt Instrument, Interest Rate, Stated Percentage						1.375%
Cash equivalents	436,800,000		436,800,000		396,300,000
Restricted cash	42,322,000		42,322,000		42,362,000
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(3,000,000)	(24,100,000)	(15,400,000)	(69,900,000)
Homebuyer Closing Costs Allowances	$ 2,200,000	$ 3,300,000	$ 4,300,000	$ 7,800,000
Homebuyer Closing Costs Allowances Percentage of Housing Revenues	0.40%	1.10%	0.50%	1.40%