Investment Securities: Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Held to Maturity
Amortized Cost	$ 69,102	$ 27,890
Gross Unrealized Gains	1,251	1,942
Gross Unrealized Losses	(244)	(5)
Estimated Fair Value	70,109	29,827
Available for Sale
Total	63,080	57,797
Gross Unrealized Gains		178
Gross Unrealized Losses		68
Estimated Fair Value		57,907
U.S. agency securities
Held to Maturity
Amortized Cost	28,760
Gross Unrealized Gains	8
Gross Unrealized Losses	(99)
Estimated Fair Value	28,669
Mortgage-backed securities, U.S. government agencies
Held to Maturity
Amortized Cost	25,913	27,161
Gross Unrealized Gains	936	1,635
Gross Unrealized Losses	(122)	(3)
Estimated Fair Value	26,727	28,793
Available for Sale
Total	63,080	57,797
Gross Unrealized Gains	210	178
Gross Unrealized Losses	114	68
Estimated Fair Value	63,176	57,907
Mortgage-backed securities, Private label residential
Held to Maturity
Amortized Cost	13,929	229
Gross Unrealized Gains	302	307
Gross Unrealized Losses	(23)	(1)
Estimated Fair Value	14,208	535
Bank issued trust preferred securities
Held to Maturity
Amortized Cost	500	500
Gross Unrealized Gains	5	0
Gross Unrealized Losses	0	(1)
Estimated Fair Value	$ 505	$ 499

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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Amount of 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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