Mortgage Loans - Other Mortgage Loans (Details) - Financial Services and Other [Member] - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016
Mortgage Loans on Real Estate, Write-down or Reserve [Line Items]
Other mortgage loans	$ 10.8	$ 15.6
Real estate owned	0.1	0.8
Total other mortgage loans and real estate owned, before loss reserves	10.9	16.4
Schedule of mortgage loss reserves
Loan loss reserves	9.4	8.7
Mortgage Loans on Real Estate [Member]
Schedule of mortgage loss reserves
Loan loss reserves	1.4	1.8
Real Estate [Member]
Schedule of mortgage loss reserves
Loan loss reserves	0.0	0.1
Obligation to Repurchase Receivables Sold [Member]
Schedule of mortgage loss reserves
Loan loss reserves	$ 8.0	$ 6.8

Reserve for mortgage loans on real estate.

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

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-Publisher FASB
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-Topic 942
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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

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