Fair Values of Financial and Nonfinancial Instruments (Details 3) (USD $)	9 Months Ended								9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Measured on a non-recurring basis	Dec. 31, 2010 Measured on a non-recurring basis	Sep. 30, 2011 Measured on a non-recurring basis Level 3 Housing inventory and inventory held-for-sale	Dec. 31, 2010 Measured on a non-recurring basis Level 3 Housing inventory and inventory held-for-sale	Sep. 30, 2011 Measured on a non-recurring basis Level 3 Other assets held-for-sale and investments in joint ventures	Dec. 31, 2010 Measured on a non-recurring basis Level 3 Other assets held-for-sale and investments in joint ventures	Sep. 30, 2011 Level 3 Housing inventory and inventory held-for-sale	Dec. 31, 2010 Level 3 Housing inventory and inventory held-for-sale	Dec. 31, 2010 Level 3 Other assets held-for-sale	Sep. 30, 2011 Level 3 Investments in joint ventures:	Dec. 31, 2010 Level 3 Investments in joint ventures:
Nonfinancial instruments measured on nonrecurring basis
Impairment charges	$ 16,185,000	$ 29,338,000							$ 13,100,000	$ 32,200,000	$ 191,000	$ 1,900,000	$ 4,100,000
Fair value of impaired assets			$ 12,415,000	$ 31,248,000	$ 11,082,000	$ 28,426,000	$ 1,333,000	$ 2,822,000			$ 1,400,000	$ 1,300,000	$ 1,400,000