Loans and Allowance for Loan Losses (Recorded Investment in Troubled Debt Restructurings by Class of Loan and Accrual Status) (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Financing Receivable, Modifications [Line Items]
Accruing	$ 8,855	$ 9,145
Nonaccrual	204	86
Total	9,059	9,231
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	2,240	2,396
Nonaccrual	136	21
Total	2,376	2,417
Commercial real estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	6,320	6,435
Nonaccrual	68	65
Total	6,388	6,500
Commercial business [Member]
Financing Receivable, Modifications [Line Items]
Accruing	215	231
Nonaccrual	0	0
Total	215	231
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Accruing	80	83
Nonaccrual	0	0
Total	$ 80	$ 83

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://fasb.org/us-gaap/role/ref/legacyRef
-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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