Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 9,565	$ 9,843	$ 9,553	$ 9,826
Provision for (Recapture of) Loan Losses	0	(250)	0	(250)
Charge- offs	(29)	(9)	(30)	(19)
Recoveries	8	6	21	33
Allowance for loan losses, Ending Allowance	9,544	9,590	9,544	9,590
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,125	1,177	1,082	1,239
Provision for (Recapture of) Loan Losses	(65)	(51)	(22)	(134)
Charge- offs	0	0	0	0
Recoveries	0	0	0	21
Allowance for loan losses, Ending Allowance	1,060	1,126	1,060	1,126
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	430	400	447	473
Provision for (Recapture of) Loan Losses	(44)	80	(61)	7
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	386	480	386	480
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	4,093	4,523	4,184	4,384
Provision for (Recapture of) Loan Losses	133	(199)	42	(55)
Charge- offs	(28)	(8)	(28)	(13)
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	4,198	4,316	4,198	4,316
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	788	636	699	619
Provision for (Recapture of) Loan Losses	(83)	59	6	76
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	705	695	705	695
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	75	100	128	130
Provision for (Recapture of) Loan Losses	21	(15)	(40)	(45)
Charge- offs	0	0	0	0
Recoveries	3	0	11	0
Allowance for loan losses, Ending Allowance	99	85	99	85
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	396	282	303	268
Provision for (Recapture of) Loan Losses	49	(14)	142	0
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	445	268	445	268
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	228	385	173	316
Provision for (Recapture of) Loan Losses	56	(289)	111	(220)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	284	96	284	96
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	0		0
Provision for (Recapture of) Loan Losses	48		48
Charge- offs	0		0
Recoveries	0		0
Allowance for loan losses, Ending Allowance	48		48
Mortgage loans, land
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	780	836	918	820
Provision for (Recapture of) Loan Losses	(94)	106	(236)	119
Charge- offs	0	0	0	(2)
Recoveries	5	5	9	10
Allowance for loan losses, Ending Allowance	691	947	691	947
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	958	859	983	939
Provision for (Recapture of) Loan Losses	(13)	98	(38)	18
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	945	957	945	957
Consumer loans, other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	129	156	121	156
Provision for (Recapture of) Loan Losses	(8)	(26)	0	(24)
Charge- offs	(1)	(1)	(2)	(4)
Recoveries	0	1	1	2
Allowance for loan losses, Ending Allowance	120	130	120	130
Commercial business loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, Beginning Allowance	563	489	515	482
Provision for (Recapture of) Loan Losses	0	1	48	8
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	$ 563	$ 490	$ 563	$ 490

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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