Other Assets, Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Other assets
Earnest money and refundable deposits	$ 474.0	$ 445.2
Insurance receivables	57.8	54.6	$ 73.1
Other receivables	73.2	81.7
Prepaid assets	36.4	36.9
Rental properties	31.8	39.2
Multi-family property held for sale		0.0
Contract Asset Insurance Renewals	33.4	0.0
Other	68.6	55.3
Other assets	818.8	712.9
Accrued expenses and other liabilities
Reserves for legal claims	412.2	408.1	419.7	$ 420.6
Employee compensation and related liabilities	205.5	252.5
Warranty liability	205.6	202.0	$ 149.4	$ 143.7
Accrued interest	35.7	14.8
Federal and state income tax liabilities	122.1	35.2
Inventory related accruals	42.2	45.5
Customer deposits	54.6	58.1
Accrued property taxes	26.1	38.0
Other	94.1	73.3
Accrued expenses and other liabilities	1,198.1	1,127.5
Other Segments [Member]
Other assets
Other assets	81.2	0.9
Accrued expenses and other liabilities
Accrued expenses and other liabilities	14.4	$ 9.9
Multifamily [Member] | Other Segments [Member]
Other assets
Multi-family property held for sale	$ 43.6