Securities (Tables)

9 Months Ended

Jun. 30, 2025

Marketable Securities [Abstract]

Amortized Cost, Estimated Fair Value, And Gross Unrealized Gains And Losses Of AFS Securities

The following tables reflect the amortized cost, estimated fair value, and gross unrealized gains and losses of AFS securities at the dates presented. The majority of our AFS securities at both dates were government guaranteed or issued by a Government Sponsored Enterprise ("GSE").

	June 30, 2025
			Gross		Gross		Estimated
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
	(Dollars in thousands)
MBS	$	874,360	$	23,527	$	312	$	897,575
GSE debentures	55,000		4		49		54,955
Corporate bonds	4,000		—		301		3,699
	$	933,360	$	23,531	$	662	$	956,229

	September 30, 2024
			Gross		Gross		Estimated
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
	(Dollars in thousands)
MBS	$	756,775	$	26,885	$	87	$	783,573
GSE debentures	69,077		228		—		69,305
Corporate bonds	4,000		—		612		3,388
	$	829,852	$	27,113	$	699	$	856,266

Schedule Of Estimated Fair Value And Gross Unrealized Losses Of Securities In Continuous Unrealized Loss Position

The following tables summarize the estimated fair value and gross unrealized losses of those AFS securities on which an unrealized loss at the dates presented was reported and the continuous unrealized loss position for less than 12 months and equal to or greater than 12 months as of the dates presented.

	June 30, 2025
	Less Than 12 Months				Equal to or Greater Than 12 Months
	Estimated		Unrealized		Estimated		Unrealized
	Fair Value		Losses		Fair Value		Losses
	(Dollars in thousands)
MBS	$	73,329	$	244	$	8,348	$	68
GSE debentures	44,951		49		—		—
Corporate bonds	—		—		3,699		301
	$	118,280	$	293	$	12,047	$	369

	September 30, 2024
	Less Than 12 Months				Equal to or Greater Than 12 Months
	Estimated		Unrealized		Estimated		Unrealized
	Fair Value		Losses		Fair Value		Losses
	(Dollars in thousands)
MBS	$	10,997	$	44	$	2,919	$	43
Corporate bonds	—		—		3,388		612
	$	10,997	$	44	$	6,307	$	655

Schedule Of Contractual Maturities

The amortized cost and estimated fair value of AFS debt securities as of June 30, 2025, by contractual maturity, are shown below.  Actual principal repayments may differ from contractual maturities due to prepayment or early call privileges by the issuer. In the case of MBS, borrowers on the underlying loans generally have the right to prepay their loans without penalty. For this reason, MBS are not included in the maturity category in the table below.

	Amortized		Estimated
	Cost		Fair Value
	(Dollars in thousands)
Five years through ten years	$	59,000	$	58,654
	59,000		58,654
MBS	874,360		897,575
	$	933,360	$	956,229

Schedule Of Taxable And Non-taxable Components Of Interest Income

The following table presents the taxable and non-taxable components of interest income on investment securities for the periods presented.

	For the Three Months Ended				For the Nine Months Ended
	June 30,				June 30,
	2025		2024		2025		2024
	(Dollars in thousands)
Taxable	$	784	$	2,255	$	2,795	$	7,113
Non-taxable	—		—		—		2
	$	784	$	2,255	$	2,795	$	7,115

Schedule Of Carrying Value Of Securities Pledged As Collateral

The following table summarizes the carrying value of securities pledged as collateral for the obligations indicated below as of the dates presented.

	June 30, 2025		September 30, 2024
	(Dollars in thousands)
Public unit deposits	$	154,802	$	108,748
Federal Reserve Bank of Kansas City ("FRB of Kansas City") borrowings	95,307		111,281
	$	250,109	$	220,029