Fair Value Measurements Fair Value Measurements - Level 3 Rollforward (Details) (USD $) In Millions, unless otherwise specified													9 Months Ended				3 Months Ended
	Jun. 30, 2014 Homebuilding [Member]	Sep. 30, 2013 Homebuilding [Member]	Jun. 30, 2014 Homebuilding [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Measurements, Recurring [Member]		Sep. 30, 2013 Homebuilding [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Measurements, Recurring [Member]		Jun. 30, 2014 Financial Services [Member]	Sep. 30, 2013 Financial Services [Member]	Jun. 30, 2014 Financial Services [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Measurements, Recurring [Member]		Sep. 30, 2013 Financial Services [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Measurements, Recurring [Member]		Jun. 30, 2014 Debt Securities [Member] Homebuilding [Member]		Jun. 30, 2014 Loans Receivable [Member] Financial Services [Member]		Jun. 30, 2014 Minimum [Member] Inventories [Member] Homebuilding [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Discount Rate																	12.00%
Other Investments	$ 20.8	$ 20.3	$ 20.8	[1]	$ 20.3	[1]
Mortgage loans held for sale							419.2	395.1	9.3	[2]	5.7	[2]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings, Description													0.5	[1]	0.7	[2]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases													0	[1]	0	[2]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements													0	[1]	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales													0	[2]	(0.5)	[2]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3													$ 0	[2]	$ 3.4	[2]

[1] In October 2012, the Company purchased defaulted debt securities which are secured by residential real estate. These securities, which are included in other assets in the consolidated balance sheets, are classified as available for sale and are reflected at fair value. At June 30, 2014, the fair value of these securities was based on a recent agreement with an outside third party to sell the securities. Unrealized gains or losses on these securities, net of tax, are recorded in accumulated other comprehensive income (loss) in the consolidated balance sheets.

[2] Mortgage loans held for sale are reflected at fair value. Interest income earned on mortgage loans held for sale is based on contractual interest rates and included in financial services interest and other income. Mortgage loans held for sale at June 30, 2014 includes $9.3 million of originated loans for which the Company elected the fair value option upon origination and which the Company has not sold into the secondary market, but plans to sell as market conditions permit. The fair value of these mortgage loans held for sale is generally calculated considering the secondary market and adjusted for the value of the underlying collateral, including interest rate risk, liquidity risk and prepayment risk.