Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			$ 9,553	$ 9,826
Provision for (Recapture of) Loan Losses	$ 0	$ (1,000)	0	(1,250)
Charge- offs	(17)	(51)	(47)	(70)
Recoveries	5	1,071	26	1,104
Allowance for loan losses, Ending Allowance	9,532	9,610	9,532	9,610
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			1,082	1,239
Provision for (Recapture of) Loan Losses	(33)	(11)	(55)	(145)
Charge- offs	0	0	0	0
Recoveries	0	0	0	21
Allowance for loan losses, Ending Allowance	1,027	1,115	1,027	1,115
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			447	473
Provision for (Recapture of) Loan Losses	21	(16)	(40)	(9)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	407	464	407	464
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			4,184	4,384
Provision for (Recapture of) Loan Losses	(15)	(1,040)	27	(1,095)
Charge- offs	0	0	(28)	(13)
Recoveries	0	1,061	0	1,061
Allowance for loan losses, Ending Allowance	4,183	4,337	4,183	4,337
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			699	619
Provision for (Recapture of) Loan Losses	(38)	17	(32)	93
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	667	712	667	712
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			128	130
Provision for (Recapture of) Loan Losses	34	(15)	(6)	(60)
Charge- offs	0	0	0	0
Recoveries	0	5	11	5
Allowance for loan losses, Ending Allowance	133	75	133	75
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			303	268
Provision for (Recapture of) Loan Losses	74	15	216	15
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	519	283	519	283
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			173	316
Provision for (Recapture of) Loan Losses	(137)	36	(26)	(184)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	147	132	147	132
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			0
Provision for (Recapture of) Loan Losses	32		80
Charge- offs	0		0
Recoveries	0		0
Allowance for loan losses, Ending Allowance	80		80
Mortgage loans, land
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			918	820
Provision for (Recapture of) Loan Losses	64	1	(172)	120
Charge- offs	(16)	(49)	(16)	(51)
Recoveries	5	5	14	15
Allowance for loan losses, Ending Allowance	744	904	744	904
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			983	939
Provision for (Recapture of) Loan Losses	1	(2)	(37)	16
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	946	955	946	955
Consumer loans, other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			121	156
Provision for (Recapture of) Loan Losses	2	6	2	(18)
Charge- offs	(1)	(2)	(3)	(6)
Recoveries	0	0	1	2
Allowance for loan losses, Ending Allowance	121	134	121	134
Commercial business loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance			515	482
Provision for (Recapture of) Loan Losses	(5)	9	43	17
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	$ 558	$ 499	$ 558	$ 499

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

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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 (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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