Inventory - Narrative (Details) (USD $)			3 Months Ended
	Jun. 30, 2012 homes	Sep. 30, 2011 homes	Jun. 30, 2012 Minimum	Jun. 30, 2011 Minimum	Jun. 30, 2012 Maximum	Jun. 30, 2011 Maximum
Real Estate Properties [Line Items]
Number of substantially completed homes	137	334
Total value of substantially completed homes	$ 28,500,000	$ 59,300,000
Discount rate			11.80%	14.60%	16.10%	16.30%
Deposits and non-refundable preacquisition costs incurred	24,651,000	20,097,000
Total remaining purchase price committed under all options	$ 197,301,000	$ 225,230,000