Investment Securities: Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Held to maturity
Amortized Cost	$ 278,585	$ 266,608
Gross Unrealized Gains	595	260
Gross Unrealized Losses	(15,202)	(17,085)
Estimated Fair Value	263,978	249,783
Available for sale
Total	56,760
Estimated Fair Value	56,678	42,250
U.S. Treasury and U.S. government agency securities
Held to maturity
Amortized Cost	170,913	170,676
Gross Unrealized Gains	92	11
Gross Unrealized Losses	(10,616)	(12,109)
Estimated Fair Value	160,389	158,578
U.S. government agencies
Held to maturity
Amortized Cost	55,517	43,995
Gross Unrealized Gains	231	4
Gross Unrealized Losses	(2,240)	(2,486)
Estimated Fair Value	53,508	41,513
Available for sale
Total	56,759	42,309
Gross Unrealized Gains	445	0
Gross Unrealized Losses	(1,363)	(894)
Estimated Fair Value	55,841	41,415
Private label residential
Held to maturity
Amortized Cost	49,563	49,335
Gross Unrealized Gains	272	245
Gross Unrealized Losses	(2,258)	(2,392)
Estimated Fair Value	47,577	47,188
Taxable municipal securities
Held to maturity
Amortized Cost	2,092	2,102
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(58)	(67)
Estimated Fair Value	2,034	2,035
Bank issued trust preferred securities
Held to maturity
Amortized Cost	500	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(30)	(31)
Estimated Fair Value	$ 470	$ 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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