Loans Receivable And Allowance For Loan Losses: Financing Receivable Credit Quality Indicators (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Sep. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	$ 1,280,911	$ 1,150,450
Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	229,274	176,116
Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	111,777	95,025
Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	557,015	536,650
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	78,739	67,091
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	7,037	8,364
Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	24,300	29,059
Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	52,941	34,354
Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	13,810	13,582
Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	25,908	26,854
Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	40,008	35,187
Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	2,469	2,128
Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	137,114	125,039
SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	519	1,001
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	1,261,296	1,132,403
Pass | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	228,870	175,687
Pass | Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	111,777	95,025
Pass | Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	543,495	522,741
Pass | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	75,340	65,249
Pass | Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	7,037	8,364
Pass | Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	23,333	29,059
Pass | Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	52,941	34,354
Pass | Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	13,810	13,557
Pass | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	25,253	25,882
Pass | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	39,700	34,709
Pass | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	2,442	2,063
Pass | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	136,810	124,712
Pass | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	488	1,001
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	13,032	10,423
Watch | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	30	38
Watch | Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Watch | Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	8,039	7,940
Watch | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	3,399	1,842
Watch | Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Watch | Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	967	0
Watch | Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Watch | Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Watch | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	505	522
Watch | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	34	19
Watch | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	27	62
Watch | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Watch | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	31	0
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	237
Special Mention | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	237
Special Mention | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Special Mention | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	6,583	7,387
Substandard | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	374	391
Substandard | Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard | Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	5,481	5,732
Substandard | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard | Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard | Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard | Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	0
Substandard | Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	25
Substandard | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	150	450
Substandard | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	274	459
Substandard | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	0	3
Substandard | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	304	327
Substandard | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	$ 0	$ 0