Other Assets and Accrued Expenses and Other Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012
Homebuilding other assets
Homebuilding other assets	$ 481.2		$ 517.4
Homebuilding [Member]
Homebuilding other assets
Insurance receivables	136.1		162.1	195.8
Earnest money and refundable deposits	100.5		98.5
Accounts and notes receivable	23.8		24.1
Prepaid assets	45.5		49.4
Rental Properties	45.8		41.3
Other Investments	20.8		20.3
Other assets	55.3		64.8
Homebuilding other assets	427.8		460.5
Homebuilding accrued expenses and other liabilities
Construction defect and other litigation liabilities	454.2		482.0	519.7		544.9
Employee compensation and related liabilities	125.5		130.2
Warranty liability	57.3	56.7	56.9	57.3	56.6	56.8
Accrued interest	33.4		34.0
Federal and state income tax liabilities	20.2		29.9
Construction Payable	37.9		46.3
Customer Deposits, Current	43.4		39.3
Accrual for Taxes Other than Income Taxes, Current	16.3		30.0
Other liabilities	34.4		37.4
Homebuilding accrued expenses and other liabilities	$ 822.6		$ 886.0