Loans Receivable - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract	Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts \| contract	6	11	29	33
Pre-Modification Outstanding Recorded Investment	$ 789	$ 1,836	$ 12,240	$ 6,114
Post-Modification Outstanding Recorded Investment	$ 789	$ 1,836	$ 12,240	$ 6,114
Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts \| contract	5	11	25	31
Pre-Modification Outstanding Recorded Investment	$ 714	$ 1,836	$ 4,909	$ 5,682
Post-Modification Outstanding Recorded Investment	$ 714	$ 1,836	$ 4,909	$ 5,682
Land - consumer lot loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts \| contract			0	1
Pre-Modification Outstanding Recorded Investment			$ 0	$ 204
Post-Modification Outstanding Recorded Investment			$ 0	$ 204
Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts \| contract			3	0
Pre-Modification Outstanding Recorded Investment			$ 7,256	$ 0
Post-Modification Outstanding Recorded Investment			$ 7,256	$ 0
HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts \| contract	1	0	1	1
Pre-Modification Outstanding Recorded Investment	$ 75	$ 0	$ 75	$ 228
Post-Modification Outstanding Recorded Investment	$ 75	$ 0	$ 75	$ 228

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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