Loans and Allowance for Loan Losses (Allowance For Loan Losses) (Detail) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Sep. 30, 2018
Changes in Allowance for Loan Losses:
Beginning balance	$ 9,323	$ 8,092
Provisions	315	462
Charge-offs	(43)	(65)
Recoveries	25	22
Ending balance	9,620	8,511
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			$ 695	$ 511
Collectively evaluated for impairment			8,925	8,812
Ending balance	9,323	8,092	9,620	9,323
Residential Real Estate [Member]
Changes in Allowance for Loan Losses:
Beginning balance	274	252
Provisions	(30)	(18)
Charge-offs	(1)	(13)
Recoveries	6	12
Ending balance	249	233
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			2	7
Collectively evaluated for impairment			247	267
Ending balance	274	252	249	274
Commercial Real Estate [Member]
Changes in Allowance for Loan Losses:
Beginning balance	6,825	5,739
Provisions	(109)	367
Charge-offs	0	0
Recoveries	0	0
Ending balance	6,716	6,106
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			654	492
Collectively evaluated for impairment			6,062	6,333
Ending balance	6,825	5,739	6,716	6,825
Multifamily [Member]
Changes in Allowance for Loan Losses:
Beginning balance	195	106
Provisions	(37)	(4)
Charge-offs	0	0
Recoveries	0	0
Ending balance	158	102
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			158	195
Ending balance	195	106	158	195
Construction [Member]
Changes in Allowance for Loan Losses:
Beginning balance	580	810
Provisions	113	93
Charge-offs	0	0
Recoveries	0	0
Ending balance	693	903
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			693	580
Ending balance	580	810	693	580
Land and Land Development [Member]
Changes in Allowance for Loan Losses:
Beginning balance	210	223
Provisions	9	(4)
Charge-offs	0	0
Recoveries	0	0
Ending balance	219	219
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			219	210
Ending balance	210	223	219	210
Commercial Business [Member]
Changes in Allowance for Loan Losses:
Beginning balance	1,041	839
Provisions	247	(23)
Charge-offs	0	0
Recoveries	0	0
Ending balance	1,288	816
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			1,288	1,041
Ending balance	1,041	839	1,288	1,041
Consumer [Member]
Changes in Allowance for Loan Losses:
Beginning balance	198	123
Provisions	122	51
Charge-offs	(42)	(52)
Recoveries	19	10
Ending balance	297	132
Ending Allowance Balance Attributable to Loans:
Individually evaluated for impairment			39	12
Collectively evaluated for impairment			258	186
Ending balance	$ 198	$ 123	$ 297	$ 198

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A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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-Publisher FASB
-Name Accounting Standards Codification
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The increase (decrease) in the allowance for credit losses related to financing receivables.

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-Publisher FASB
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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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-Publisher FASB
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-Topic 310
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Amount of direct write-downs of financing receivables charged against the allowance.

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-Publisher FASB
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