Loans and Allowance for Loan Losses (Components Of Recorded Investment In Loans For Each Portfolio Class) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Recorded Investment in Loans:
Principal loan balance	$ 572,605	$ 525,944
Accrued interest receivable	1,827	1,451
Net deferred loan origination fees and costs	161	(211)
Recorded investment in loans	574,593	527,184
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	10,761	11,361
Collectively evaluated for impairment	563,832	515,823
Ending balance	574,593	527,184
Residential Real Estate [Member]
Recorded Investment in Loans:
Principal loan balance	173,620	178,364
Accrued interest receivable	482	505
Net deferred loan origination fees and costs	79	158
Recorded investment in loans	174,181	179,027
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	4,589	4,342
Collectively evaluated for impairment	169,592	174,685
Ending balance	174,181	179,027
Commercial Real Estate [Member]
Recorded Investment in Loans:
Principal loan balance	254,871	217,378
Accrued interest receivable	844	592
Net deferred loan origination fees and costs	(97)	(254)
Recorded investment in loans	255,618	217,716
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	5,464	6,298
Collectively evaluated for impairment	250,154	211,418
Ending balance	255,618	217,716
Multifamily [Member]
Recorded Investment in Loans:
Principal loan balance	18,696	18,431
Accrued interest receivable	33	38
Net deferred loan origination fees and costs	(15)	(17)
Recorded investment in loans	18,714	18,452
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	18,714	18,452
Ending balance	18,714	18,452
Construction [Member]
Recorded Investment in Loans:
Principal loan balance	32,948	30,337
Accrued interest receivable	175	95
Net deferred loan origination fees and costs	40	(126)
Recorded investment in loans	33,163	30,306
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	33,163	30,306
Ending balance	33,163	30,306
Land and Land development [Member]
Recorded Investment in Loans:
Principal loan balance	9,303	11,137
Accrued interest receivable	22	23
Net deferred loan origination fees and costs	4	4
Recorded investment in loans	9,329	11,164
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	314	241
Collectively evaluated for impairment	9,015	10,923
Ending balance	9,329	11,164
Commercial Business [Member]
Recorded Investment in Loans:
Principal loan balance	52,411	41,967
Accrued interest receivable	213	143
Net deferred loan origination fees and costs	170	37
Recorded investment in loans	52,794	42,147
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	198	231
Collectively evaluated for impairment	52,596	41,916
Ending balance	52,794	42,147
Consumer [Member]
Recorded Investment in Loans:
Principal loan balance	30,756	28,330
Accrued interest receivable	58	55
Net deferred loan origination fees and costs	(20)	(13)
Recorded investment in loans	30,794	28,372
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	196	249
Collectively evaluated for impairment	30,598	28,123
Ending balance	$ 30,794	$ 28,372

Interest Receivable, Loans Receivable

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=d3e107314-111719

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts 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
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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