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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 11,890	$ 9,741	$ 9,690	$ 9,530
Provision for (Recapture of) Loan Losses	1,000	0	3,200	0
Charge- offs	(1)	(141)	(27)	(157)
Recoveries	5	31	31	258
Allowance for loan losses, Ending Allowance	12,894	9,631	12,894	9,631
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,149	1,154	1,167	1,086
Provision for (Recapture of) Loan Losses	14	(36)	(7)	(35)
Charge- offs	0	0	0	0
Recoveries	0	0	3	67
Allowance for loan losses, Ending Allowance	1,163	1,118	1,163	1,118
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	595	470	481	433
Provision for (Recapture of) Loan Losses	70	(32)	184	5
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	665	438	665	438
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	5,762	4,122	4,154	4,248
Provision for (Recapture of) Loan Losses	957	(70)	2,560	(346)
Charge- offs	0	0	0	0
Recoveries	0	0	5	150
Allowance for loan losses, Ending Allowance	6,719	4,052	6,719	4,052
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	697	666	755	671
Provision for (Recapture of) Loan Losses	110	36	47	31
Charge- offs	0	0	0	0
Recoveries	0	0	5	0
Allowance for loan losses, Ending Allowance	807	702	807	702
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	204	249	212	178
Provision for (Recapture of) Loan Losses	(40)	(28)	(48)	43
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	164	221	164	221
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	423	384	338	563
Provision for (Recapture of) Loan Losses	(119)	0	(34)	(179)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	304	384	304	384
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	394	272	375	135
Provision for (Recapture of) Loan Losses	(76)	95	(57)	232
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	318	367	318	367
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	80	244	67	49
Provision for (Recapture of) Loan Losses	27	(118)	40	77
Charge- offs	0		0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	107	126	107	126
Mortgage loans, land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	678	649	697	844
Provision for (Recapture of) Loan Losses	(41)	48	(70)	(155)
Charge- offs	0	(46)	0	(46)
Recoveries	5	5	15	13
Allowance for loan losses, Ending Allowance	642	656	642	656
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	656	667	623	649
Provision for (Recapture of) Loan Losses	(24)	(21)	9	1
Charge- offs	0	(1)	0	(5)
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	632	645	632	645
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	78	112	99	117
Provision for (Recapture of) Loan Losses	(4)	(25)	(17)	(29)
Charge- offs	(1)	(1)	(12)	(4)
Recoveries	0	1	3	3
Allowance for loan losses, Ending Allowance	73	87	73	87
Commercial business loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,174	752	722	557
Provision for (Recapture of) Loan Losses	126	151	593	355
Charge- offs	0	(93)	(15)	(102)
Recoveries	0	25	0	25
Allowance for loan losses, Ending Allowance	$ 1,300	$ 835	$ 1,300	$ 835

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 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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