Subsequent Event Subsequent Event (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2013 RegentHomes [Member] Subsequent Event [Member]	Oct. 31, 2013 RegentHomes [Member] Subsequent Event [Member] Lot Home
Subsequent Event [Line Items]
Business Acquisition, Effective Date of Acquisition				Oct. 04, 2013
Payments to Acquire Businesses, Net of Cash Acquired	$ 9.4	$ 96.5	$ 0	$ 35.0
Business Acquisition, Number of Homes Acquired					240
Business Acquisition, Number of Finished Lots Acquired					300
Business Acquisition, Number of Lots Under Option Contracts					600
Business Acquisition, Sales Order Backlog Acquired (Homes)					213
Business Acquisition, Sales Order Backlog Acquired (Value)					$ 31.1