Inventory (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended						6 Months Ended		12 Months Ended
	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Apr. 30, 2012	Apr. 30, 2011	Oct. 31, 2011
Total Inventory
Inventory	$ 3,767,877		$ 3,416,723				$ 3,767,877		$ 3,416,723
Inventory impairment charges and expensing of costs that not to be recoverable
Inventory impairments and write-offs	2,008				12,922		10,128	18,048
Land controlled for future communities [Member]
Total Inventory
Inventory	41,442		46,581				41,442		46,581
Inventory impairment charges and expensing of costs that not to be recoverable
Inventory impairments and write-offs	(552)				2,197		225	1,848
Land owned for future communities [Member]
Total Inventory
Inventory	1,046,240		979,145				1,046,240		979,145
Inventory impairment charges and expensing of costs that not to be recoverable
Inventory impairments and write-offs	0				0		918	0
Operating communities [Member]
Total Inventory
Inventory	2,680,195		2,390,997				2,680,195		2,390,997
Inventory impairment charges and expensing of costs that not to be recoverable
Inventory impairments and write-offs	$ 2,560	$ 6,425	$ 710	$ 175	$ 10,725	$ 5,475	$ 8,985	$ 16,200	$ 17,085