Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 15,817	$ 13,703
Provision for (Recapture of) Credit Losses	379	525
Charge- offs	(2)	0
Recoveries	0	1
Allowance for loan losses, Ending Allowance	16,655	14,229
Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	461
One-to four-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	2,417	1,658
Provision for (Recapture of) Credit Losses	87	230
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	2,096	1,888
One-to four-family \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(408)
Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,156	855
Provision for (Recapture of) Credit Losses	164	16
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	1,200	871
Multi-family \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(120)
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	7,209	6,682
Provision for (Recapture of) Credit Losses	107	112
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	6,822	6,794
Commercial real estate \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(494)
Construction-custom & owner/builder
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	750	675
Provision for (Recapture of) Credit Losses	(58)	(2)
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	1,234	673
Construction-custom & owner/builder \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	542
Construction-speculative one-to four-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	148	130
Provision for (Recapture of) Credit Losses	0	(5)
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	132	125
Construction-speculative one-to four-family \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(16)
Construction-commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	316	343
Provision for (Recapture of) Credit Losses	(62)	(20)
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	430	323
Construction-commercial \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	176
Construction-multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	602	447
Provision for (Recapture of) Credit Losses	(71)	130
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	735	577
Construction-multi-family \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	204
Construction-land development
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	274	233
Provision for (Recapture of) Credit Losses	(1)	(11)
Recoveries	0	0
Allowance for loan losses, Ending Allowance	298	222
Construction-land development \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	25
Land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	406	397
Provision for (Recapture of) Credit Losses	33	(14)
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	757	383
Land \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	318
Home equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	519	440
Provision for (Recapture of) Credit Losses	10	53
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	286	493
Home equity \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(243)
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	53	42
Provision for (Recapture of) Credit Losses	2	4
Charge- offs		0
Recoveries	0	1
Allowance for loan losses, Ending Allowance	46	47
Consumer loans, other \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	(7)
Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,967	1,801
Provision for (Recapture of) Credit Losses	168	32
Charge- offs		0
Recoveries	0	0
Allowance for loan losses, Ending Allowance	2,619	$ 1,833
Commercial business \| Impact of Adopting CECL (ASU 2016-13)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	484
SBA PPP
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 0

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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