Loans and Allowance for Loan Losses (Recorded Investment in Troubled Debt Restructurings by Class of Loan and Accrual Status) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Financing Receivable, Modifications [Line Items]
Accruing	$ 6,921	$ 7,486
Nonaccrual	1,480	1,632
Total	8,401	9,118
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	2,636	2,590
Nonaccrual	77	0
Total	2,713	2,590
Commercial real estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	4,041	4,692
Nonaccrual	1,318	1,512
Total	5,359	6,204
Commercial business [Member]
Financing Receivable, Modifications [Line Items]
Accruing	113	95
Nonaccrual	85	120
Total	198	215
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Accruing	99	109
Nonaccrual	0	0
Total	99	$ 109
Land and land development [Member]
Financing Receivable, Modifications [Line Items]
Accruing	32
Nonaccrual	0
Total	$ 32

Financing Receivable, Modifications, Recorded Investment, Accruing

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- Definition

Financing Receivable, Modifications, Recorded Investment, Nonaccrual

+ References

No definition available.

+ 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.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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