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, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 13,434	$ 11,890	$ 13,414	$ 9,690
Provision for (Recapture of) Loan Losses	0	1,000	0	3,200
Charge- offs	0	(1)	(3)	(27)
Recoveries	35	5	58	31
Allowance for loan losses, Ending Allowance	13,469	12,894	13,469	12,894
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,151	1,149	1,163	1,167
Provision for (Recapture of) Loan Losses	(9)	14	(21)	(7)
Charge- offs	0	0	0	0
Recoveries	0	0	0	3
Allowance for loan losses, Ending Allowance	1,142	1,163	1,142	1,163
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	784	595	718	481
Provision for (Recapture of) Loan Losses	26	70	92	184
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	810	665	810	665
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	7,238	5,762	7,144	4,154
Provision for (Recapture of) Loan Losses	(277)	957	(183)	2,560
Charge- offs	0	0	0	0
Recoveries	0	0	0	5
Allowance for loan losses, Ending Allowance	6,961	6,719	6,961	6,719
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	695	697	832	755
Provision for (Recapture of) Loan Losses	(91)	110	(228)	47
Charge- offs	0	0	0	0
Recoveries	0	0	0	5
Allowance for loan losses, Ending Allowance	604	807	604	807
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	148	204	158	212
Provision for (Recapture of) Loan Losses	36	(40)	26	(48)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	184	164	184	164
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	714	423	420	338
Provision for (Recapture of) Loan Losses	44	(119)	338	(34)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	758	304	758	304
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	323	394	238	375
Provision for (Recapture of) Loan Losses	125	(76)	210	(57)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	448	318	448	318
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	19	80	133	67
Provision for (Recapture of) Loan Losses	12	27	(102)	40
Charge- offs	0		0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	31	107	31	107
Mortgage loans, land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	407	678	572	697
Provision for (Recapture of) Loan Losses	(58)	(41)	(233)	(70)
Charge- offs	0	0	0	0
Recoveries	35	5	45	15
Allowance for loan losses, Ending Allowance	384	642	384	642
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	552	656	593	623
Provision for (Recapture of) Loan Losses	(1)	(24)	(42)	9
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	551	632	551	632
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	56	78	71	99
Provision for (Recapture of) Loan Losses	0	(4)	(18)	(17)
Charge- offs	0	(1)	(1)	(12)
Recoveries	0	0	4	3
Allowance for loan losses, Ending Allowance	56	73	56	73
Commercial business loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,347	1,174	1,372	722
Provision for (Recapture of) Loan Losses	193	126	161	593
Charge- offs	0	0	(2)	(15)
Recoveries	0	0	9	0
Allowance for loan losses, Ending Allowance	$ 1,540	$ 1,300	$ 1,540	$ 1,300

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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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.

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