Investment Securities: Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Held to maturity
Amortized Cost	$ 277,911	$ 266,608
Gross Unrealized Gains	612	260
Gross Unrealized Losses	(13,431)	(17,085)
Estimated Fair Value	265,092	249,783
Available for sale
Total	55,454
Estimated Fair Value	55,688	42,250
U.S. Treasury and U.S. government agency securities
Held to maturity
Amortized Cost	171,148	170,676
Gross Unrealized Gains	118	11
Gross Unrealized Losses	(9,244)	(12,109)
Estimated Fair Value	162,022	158,578
U.S. government agencies
Held to maturity
Amortized Cost	54,522	43,995
Gross Unrealized Gains	234	4
Gross Unrealized Losses	(2,008)	(2,486)
Estimated Fair Value	52,748	41,513
Available for sale
Total	55,454	42,309
Gross Unrealized Gains	397	0
Gross Unrealized Losses	(1,013)	(894)
Estimated Fair Value	54,838	41,415
Private label residential
Held to maturity
Amortized Cost	49,660	49,335
Gross Unrealized Gains	260	245
Gross Unrealized Losses	(2,103)	(2,392)
Estimated Fair Value	47,817	47,188
Taxable municipal securities
Held to maturity
Amortized Cost	2,081	2,102
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(48)	(67)
Estimated Fair Value	2,033	2,035
Bank issued trust preferred securities
Held to maturity
Amortized Cost	500	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(28)	(31)
Estimated Fair Value	$ 472	$ 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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