Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 9,690	$ 9,530
Provision for (Recapture of) Loan Losses	200	0
Charge- offs	(25)	(2)
Recoveries	17	5
Allowance for loan losses, Ending Allowance	9,882	9,533
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,167	1,086
Provision for (Recapture of) Loan Losses	(104)	73
Charge- offs	0	0
Recoveries	2	0
Allowance for loan losses, Ending Allowance	1,065	1,159
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	481	433
Provision for (Recapture of) Loan Losses	18	16
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	499	449
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	4,154	4,248
Provision for (Recapture of) Loan Losses	252	(9)
Charge- offs	0	0
Recoveries	4	0
Allowance for loan losses, Ending Allowance	4,410	4,239
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	755	671
Provision for (Recapture of) Loan Losses	(6)	(28)
Charge- offs	0	0
Recoveries	5	0
Allowance for loan losses, Ending Allowance	754	643
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	212	178
Provision for (Recapture of) Loan Losses	36	28
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	248	206
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	338	563
Provision for (Recapture of) Loan Losses	65	(177)
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	403	386
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	375	135
Provision for (Recapture of) Loan Losses	(42)	74
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	333	209
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	67	49
Provision for (Recapture of) Loan Losses	(19)	94
Charge- offs	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	48	143
Mortgage loans, land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	697	844
Provision for (Recapture of) Loan Losses	(48)	(91)
Charge- offs	0	0
Recoveries	5	4
Allowance for loan losses, Ending Allowance	654	757
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	623	649
Provision for (Recapture of) Loan Losses	(14)	17
Charge- offs	0	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	609	666
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	99	117
Provision for (Recapture of) Loan Losses	(3)	(15)
Charge- offs	(10)	(2)
Recoveries	1	1
Allowance for loan losses, Ending Allowance	87	101
Commercial business loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	722	557
Provision for (Recapture of) Loan Losses	65	18
Charge- offs	(15)	0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	$ 772	$ 575

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

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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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