Capitalized Interest Capitalized Interest (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2011
Capitalized Interest [Line Items]
Interest Costs Incurred	$ 185.8	[1]	$ 172.8	[1]	$ 124.1	[1]
Real Estate Inventory, Capitalized Interest Costs [Roll Forward]
Real Estate Inventory, Capitalized Interest Costs	198.5		137.1		82.3		79.2
Interest Expense	0		(7.1)		(26.9)
Real Estate Inventory, Capitalized Interest Costs, Cost of Sales	(123.1)		(110.2)		(94.0)
Capitalized Interest Costs Written Off With Inventory Impairments	(1.3)		(0.7)		(0.1)
Financial Services [Member]
Capitalized Interest [Line Items]
Interest Costs Incurred	$ 4.5		$ 4.6		$ 3.3

[1] Interest incurred includes interest incurred on the Company's financial services mortgage repurchase facility of $4.5 million, $4.6 million and $3.3 million in fiscal 2014, 2013 and 2012, respectively.