Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 13,469	$ 13,414
Provision for (Recapture of) Loan Losses	0	0
Charge- offs	(1)	0
Recoveries	0	18
Allowance for loan losses, Ending Allowance	13,468	13,432
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,154	1,163
Provision for (Recapture of) Loan Losses	83	(28)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	1,237	1,135
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	765	718
Provision for (Recapture of) Loan Losses	(17)	39
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	748	757
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	6,813	7,144
Provision for (Recapture of) Loan Losses	(6)	(8)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	6,807	7,136
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	644	832
Provision for (Recapture of) Loan Losses	27	(62)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	671	770
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	188	158
Provision for (Recapture of) Loan Losses	(35)	24
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	153	182
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	784	420
Provision for (Recapture of) Loan Losses	(191)	138
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	593	558
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	436	238
Provision for (Recapture of) Loan Losses	24	(52)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	460	186
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	124	133
Provision for (Recapture of) Loan Losses	33	(10)
Charge- offs	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	157	123
Mortgage loans, land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	470	572
Provision for (Recapture of) Loan Losses	(35)	(103)
Charge- offs	0	0
Recoveries	0	5
Allowance for loan losses, Ending Allowance	435	474
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	528	593
Provision for (Recapture of) Loan Losses	4	12
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	532	605
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	50	71
Provision for (Recapture of) Loan Losses	(1)	(18)
Charge- offs	(1)	0
Recoveries	0	4
Allowance for loan losses, Ending Allowance	48	57
Commercial business loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,513	1,372
Provision for (Recapture of) Loan Losses	114	68
Charge- offs	0	0
Recoveries	0	9
Allowance for loan losses, Ending Allowance	1,627	$ 1,449
SBA PPP Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	0
Allowance for loan losses, Ending Allowance	$ 0

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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