Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2017	Dec. 31, 2016
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	0
Charge- offs	(1)	(10)
Recoveries	13	27
Allowance for loan losses, Ending Allowance	9,565	9,843
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	43	(83)
Charge- offs	0	0
Recoveries	0	21
Allowance for loan losses, Ending Allowance	1,125	1,177
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	(17)	(73)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	430	400
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	(91)	144
Charge- offs	0	(5)
Recoveries	0	0
Allowance for loan losses, Ending Allowance	4,093	4,523
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	89	17
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	788	636
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	(61)	(30)
Charge- offs	0	0
Recoveries	8	0
Allowance for loan losses, Ending Allowance	75	100
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	93	14
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	396	282
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	55	69
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	228	385
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	(142)	13
Charge- offs	0	(2)
Recoveries	4	5
Allowance for loan losses, Ending Allowance	780	836
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	(25)	(80)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	958	859
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	8	2
Charge- offs	(1)	(3)
Recoveries	1	1
Allowance for loan losses, Ending Allowance	129	156
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	48	7
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	$ 563	$ 489

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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- Definition

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

+ References

No definition available.

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- Definition

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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