Investment Securities: Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Sep. 30, 2022
Held to maturity
Amortized Cost	$ 275,053	$ 266,608
Gross Unrealized Gains	268	260
Gross Unrealized Losses	(14,850)	(17,085)
Estimated Fair Value	260,471	249,783
Available for sale
Total	44,772
Estimated Fair Value	44,679	42,250
U.S. Treasury and U.S. government agency securities
Held to maturity
Amortized Cost	171,385	170,676
Gross Unrealized Gains	0	11
Gross Unrealized Losses	(9,927)	(12,109)
Estimated Fair Value	161,458	158,578
U.S. government agencies
Held to maturity
Amortized Cost	53,347	43,995
Gross Unrealized Gains	10	4
Gross Unrealized Losses	(2,529)	(2,486)
Estimated Fair Value	50,828	41,513
Available for sale
Total	44,772	42,309
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(930)	(894)
Estimated Fair Value	43,842	41,415
Private label residential
Held to maturity
Amortized Cost	48,025	49,335
Gross Unrealized Gains	258	245
Gross Unrealized Losses	(2,295)	(2,392)
Estimated Fair Value	45,988	47,188
Taxable municipal securities
Held to maturity
Amortized Cost	1,796	2,102
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(47)	(67)
Estimated Fair Value	1,749	2,035
Bank issued trust preferred securities
Held to maturity
Amortized Cost	500	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(52)	(31)
Estimated Fair Value	$ 448	$ 469

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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