Loans Receivable And Allowance For Loan Losses: Schedule of Loans receivable and Loans held for sale (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 1,008,038	$ 991,376
Undisbursed portion of construction loans in process	82,172	92,226
Deferred loan origination fees, net	2,834	2,798
Allowance for loan losses	9,882	9,690
Less: Loans in process, Deferred fees and Allowance for loan losses	94,888	104,714
Loans receivable, net	$ 913,150	$ 886,662	[1]
Ratio of loan category to total loans receivable (percent)	100.00%	99.99109%
Total mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 891,052	$ 882,110
Ratio of loan category to total loans receivable (percent)	88.40%	89.00%
Mortgage loans, one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 129,373	$ 132,661
Ratio of loan category to total loans receivable (percent)	12.80%	13.40%
Mortgage loans excluded	$ 5,420	$ 6,071
Mortgage loans, multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 78,326	$ 76,036
Ratio of loan category to total loans receivable (percent)	7.80%	7.70%
Mortgage loans, commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 439,024	$ 419,117
Ratio of loan category to total loans receivable (percent)	43.60%	42.30%
Mortgage loans, construction - custom and owner/builder
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 124,530	$ 128,848
Ratio of loan category to total loans receivable (percent)	12.40%	13.00%
Mortgage loans, construction - speculative one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 18,764	$ 16,445
Ratio of loan category to total loans receivable (percent)	1.90%	1.70%
Mortgage loans, construction – commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 36,670	$ 39,566
Ratio of loan category to total loans receivable (percent)	3.60%	4.00%
Mortgage loans, construction - Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 33,290	$ 36,263
Ratio of loan category to total loans receivable (percent)	3.20%	3.60%
Mortgage loans, construction - Land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 1,656	$ 2,404
Ratio of loan category to total loans receivable (percent)	0.20%	0.20%
Mortgage loans, land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 29,419	$ 30,770
Ratio of loan category to total loans receivable (percent)	2.90%	3.10%
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	$ 43,196	$ 44,502
Ratio of loan category to total loans receivable (percent)	4.30%	4.50%
Consumer loans, home equity and second mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	$ 39,103	$ 40,190
Ratio of loan category to total loans receivable (percent)	3.90%	4.10%
Consumer loans, other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Consumer loans	$ 4,093	$ 4,312
Ratio of loan category to total loans receivable (percent)	0.40%	0.40%
Commercial business loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial business loans	$ 73,790	$ 64,764
Ratio of loan category to total loans receivable (percent)	7.30%	6.50%
Consumer loans excluded	$ 0	$ 0

[1] Derived from audited consolidated financial statements.