Loans Receivable And Allowance For Loan Losses: Financing Receivable Credit Quality Indicators (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	$ 1,229,650	$ 1,150,450
Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	216,639	176,116
Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	103,870	95,025
Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	547,876	536,650
Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	71,750	67,091
Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	7,785	8,364
Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	23,145	29,059
Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	50,758	34,354
Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	14,250	13,582
Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	24,520	26,854
Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	36,896	35,187
Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	2,283	2,128
Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	129,306	125,039
SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	572	1,001
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	1,210,537	1,132,403
Pass | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	216,226	175,687
Pass | Mortgage loans, multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	103,870	95,025
Pass | Mortgage loans, commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	534,258	522,741
Pass | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	68,505	65,249
Pass | Mortgage loans, construction - speculative one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	7,785	8,364
Pass | Mortgage loans, construction – commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	23,145	29,059
Pass | Mortgage loans, construction - Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	50,758	34,354
Pass | Mortgage loans, construction - Land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	14,231	13,557
Pass | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	23,551	25,882
Pass | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	36,416	34,709
Pass | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	2,255	2,063
Pass | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	128,997	124,712
Pass | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	540	1,001
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	11,984	10,423
Watch | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	33	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	8,103	7,940
Watch | Mortgage loans, construction - custom and owner/builder
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	3,245	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	0	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	510	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	32	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	7,129	7,387
Substandard | Mortgage loans, one-to-four family
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	380	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	5,515	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	19	25
Substandard | Mortgage loans, land
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	459	450
Substandard | Consumer loans, home equity and second mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	446	459
Substandard | Consumer loans, other
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	1	3
Substandard | Commercial business loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	309	327
Substandard | SBA PPP Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans receivable	$ 0	$ 0