Inventory Inventory (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended							9 Months Ended		12 Months Ended
	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Jul. 31, 2012	Jul. 31, 2011	Oct. 31, 2011
Number of Operating Communities Tested	115	115	113	114	129	142	143
Number of Communities Impaired	4	2	8	3	2	9	6
Fair Value of the Impaired Inventory	$ 6,609	$ 22,962	$ 49,758	$ 3,367	$ 867	$ 40,765	$ 56,105
Inventory Write-down	3,120				16,812			13,249	34,861
Operating communities [Member]
Inventory Write-down	$ 2,685	$ 2,560	$ 6,425	$ 710	$ 175	$ 10,725	$ 5,475	$ 11,670	$ 16,375	$ 17,085