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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 9,741	$ 9,544	$ 9,530	$ 9,553
Provision for (Recapture of) Loan Losses	0	0	0	0
Charge- offs	(141)	(17)	(157)	(47)
Recoveries	31	5	258	26
Allowance for loan losses, Ending Allowance	9,631	9,532	9,631	9,532
Mortgage loans, one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,154	1,060	1,086	1,082
Provision for (Recapture of) Loan Losses	(36)	(33)	(35)	(55)
Charge- offs	0	0	0	0
Recoveries	0	0	67	0
Allowance for loan losses, Ending Allowance	1,118	1,027	1,118	1,027
Mortgage loans, multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	470	386	433	447
Provision for (Recapture of) Loan Losses	(32)	21	5	(40)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	438	407	438	407
Mortgage loans, commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	4,122	4,198	4,248	4,184
Provision for (Recapture of) Loan Losses	(70)	(15)	(346)	27
Charge- offs	0	0	0	(28)
Recoveries	0	0	150	0
Allowance for loan losses, Ending Allowance	4,052	4,183	4,052	4,183
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	666	705	671	699
Provision for (Recapture of) Loan Losses	36	(38)	31	(32)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	702	667	702	667
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	249	99	178	128
Provision for (Recapture of) Loan Losses	(28)	34	43	(6)
Charge- offs	0	0	0	0
Recoveries	0	0	0	11
Allowance for loan losses, Ending Allowance	221	133	221	133
Mortgage loans, construction – commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	384	445	563	303
Provision for (Recapture of) Loan Losses	0	74	(179)	216
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	384	519	384	519
Mortgage loans, construction - Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	272	284	135	173
Provision for (Recapture of) Loan Losses	95	(137)	232	(26)
Charge- offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	367	147	367	147
Mortgage loans, construction - Land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	244	48	49
Provision for (Recapture of) Loan Losses	(118)	32	77	80
Charge- offs	0		0	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	126	80	126	80
Mortgage loans, land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	649	691	844	918
Provision for (Recapture of) Loan Losses	48	64	(155)	(172)
Charge- offs	(46)	(16)	(46)	(16)
Recoveries	5	5	13	14
Allowance for loan losses, Ending Allowance	656	744	656	744
Consumer loans, home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	667	945	649	983
Provision for (Recapture of) Loan Losses	(21)	1	1	(37)
Charge- offs	(1)	0	(5)	0
Recoveries	0	0	0	0
Allowance for loan losses, Ending Allowance	645	946	645	946
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	112	120	117	121
Provision for (Recapture of) Loan Losses	(25)	2	(29)	2
Charge- offs	(1)	(1)	(4)	(3)
Recoveries	1	0	3	1
Allowance for loan losses, Ending Allowance	87	121	87	121
Commercial business loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	752	563	557	515
Provision for (Recapture of) Loan Losses	151	(5)	355	43
Charge- offs	(93)	0	(102)	0
Recoveries	25	0	25	0
Allowance for loan losses, Ending Allowance	$ 835	$ 558	$ 835	$ 558

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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