Available-for-sale Securities - Amortized cost, gross unrealized gains, gross unrealized losses, ACL, and approximate fair value of securities available for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	$ 463,268	$ 475,395
Gross Unrealized Gains	2,620	3,128
Gross Unrealized Losses	(15,113)	(17,679)
Allowance for Credit Losses	0	0
Estimated Fair Value	450,775	460,844
Obligations of states and political subdivisions
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	24,546	26,030
Gross Unrealized Gains	18	5
Gross Unrealized Losses	(1,180)	(1,772)
Allowance for Credit Losses	0	0
Estimated Fair Value	23,384	24,263
Corporate obligations
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	28,228	31,199
Gross Unrealized Gains	112	75
Gross Unrealized Losses	(268)	(632)
Allowance for Credit Losses	0	0
Estimated Fair Value	28,072	30,642
Asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	42,011	42,059
Gross Unrealized Gains	404	567
Gross Unrealized Losses	(109)	(145)
Allowance for Credit Losses	0	0
Estimated Fair Value	42,306	42,481
Other securities
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	2,993	4,007
Gross Unrealized Gains	9	10
Gross Unrealized Losses	(47)	(53)
Allowance for Credit Losses	0	0
Estimated Fair Value	2,955	3,964
Debt securities
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	97,778	103,295
Gross Unrealized Gains	543	657
Gross Unrealized Losses	(1,604)	(2,602)
Allowance for Credit Losses	0	0
Estimated Fair Value	96,717	101,350
Residential MBS issued by governmental sponsored enterprises (GSEs)
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	148,840	138,377
Gross Unrealized Gains	1,557	1,623
Gross Unrealized Losses	(4,390)	(5,005)
Allowance for Credit Losses	0	0
Estimated Fair Value	146,007	134,995
Commercial MBS issued by GSEs
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	103,148	96,377
Gross Unrealized Gains	291	446
Gross Unrealized Losses	(4,553)	(4,821)
Allowance for Credit Losses	0	0
Estimated Fair Value	98,886	92,002
CMOs issued by GSEs
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	113,502	137,346
Gross Unrealized Gains	229	402
Gross Unrealized Losses	(4,566)	(5,251)
Allowance for Credit Losses	0	0
Estimated Fair Value	109,165	132,497
MBS and CMOs
Debt Securities, Available-for-Sale [Line Items]
Total AFS securities, Amortized Cost	365,490	372,100
Gross Unrealized Gains	2,077	2,471
Gross Unrealized Losses	(13,509)	(15,077)
Allowance for Credit Losses	0	0
Estimated Fair Value	$ 354,058	$ 359,494

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, before tax, of unrealized loss 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 excluding accrued interest, of allowance for credit loss 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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Amortized cost excluding accrued interest, before allowance for credit loss, 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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