Inventory - Summary of Interests in Lot Option Agreements (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011
Real Estate Properties [Line Items]
Deposits and non-refundable preacquisition costs incurred	$ 24,651	$ 20,097
Remaining obligations	197,301	225,230
Land not owned under option agreements	14,078	11,753
Consolidated VIEs
Real Estate Properties [Line Items]
Deposits and non-refundable preacquisition costs incurred	7,191	6,201
Remaining obligations	3,347	1,214
Land not owned under option agreements	10,537	7,415
Consolidated Entity Excluding Variable Interest Entities (VIE)
Real Estate Properties [Line Items]
Deposits and non-refundable preacquisition costs incurred	859	164
Remaining obligations	2,682	4,175
Land not owned under option agreements	3,541	4,338
Unconsolidated Entities
Real Estate Properties [Line Items]
Deposits and non-refundable preacquisition costs incurred	16,601	13,732
Remaining obligations	191,272	219,841
Land not owned under option agreements	$ 0	$ 0