Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 9,530	$ 9,553
Provision for (Recapture of) Loan Losses	0	0
Charge- offs	(2)	(1)
Recoveries	5	13
Allowance for loan losses, Ending Allowance	9,533	9,565
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,086	1,082
Provision for (Recapture of) Loan Losses	73	43
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	1,159	1,125
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	433	447
Provision for (Recapture of) Loan Losses	16	(17)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	449	430
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	4,248	4,184
Provision for (Recapture of) Loan Losses	(9)	(91)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	4,239	4,093
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	671	699
Provision for (Recapture of) Loan Losses	(28)	89
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	643	788
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	178	128
Provision for (Recapture of) Loan Losses	28	(61)
Charge- offs	0	0
Recoveries	0	8
Allowance for loan losses, Ending Allowance	206	75
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	563	303
Provision for (Recapture of) Loan Losses	(177)	93
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	386	396
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	135	173
Provision for (Recapture of) Loan Losses	74	55
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	209	228
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	49
Provision for (Recapture of) Loan Losses	94
Charge- offs	0
Recoveries	0
Allowance for loan losses, Ending Allowance	143
Mortgage loans, land
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	844	918
Provision for (Recapture of) Loan Losses	(91)	(142)
Charge- offs	0	0
Recoveries	4	4
Allowance for loan losses, Ending Allowance	757	780
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	649	983
Provision for (Recapture of) Loan Losses	17	(25)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	666	958
Consumer loans, other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	117	121
Provision for (Recapture of) Loan Losses	(15)	8
Charge- offs	(2)	(1)
Recoveries	1	1
Allowance for loan losses, Ending Allowance	101	129
Commercial business loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	557	515
Provision for (Recapture of) Loan Losses	18	48
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	$ 575	$ 563

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

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- Definition

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

+ References

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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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No definition available.

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

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- Definition

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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