Capitalized Interest (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Rollforward of capitalized interest
Capitalized interest, beginning of period	$ 137.1		$ 82.3
Interest incurred	49.3	[1]	38.1	[1]
Interest expensed:
Directly to interest expense	0		4.2
Amortized to cost of sales	(25.3)		(24.9)
Capitalized interest, end of period	161.1		91.3
Financial Services [Member]
Rollforward of capitalized interest
Interest incurred	$ 0.9		$ 1.0

[1] Interest incurred includes interest incurred on the Company's financial services mortgage repurchase facility of $0.9 million and $1.0 million in the three months ended December 31, 2013 and 2012, respectively.