Loans and Allowance for Credit Losses - Classes of loans (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	$ 4,032,594	$ 3,978,393
Loans in Process	(332,633)	(359,196)
Deferred loan fees, net	(282)	(299)
Allowance for credit losses	(49,122)	(47,820)	$ (37,418)	$ (33,192)
Total loans	$ 3,650,557	$ 3,571,078
Number of purchased participation loans	83	86
Purchased participation loans	$ 162,700	$ 155,600
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	1,134,604	1,133,417
Allowance for credit losses	(14,846)	(15,641)	(11,937)	(8,908)
Construction Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	565,525	550,052
Allowance for credit losses	(2,856)	(2,664)	(2,503)	(2,220)
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	1,564,147	1,562,379
Allowance for credit losses	(25,022)	(22,838)	(17,886)	(16,838)
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	135,263	133,515
Allowance for credit losses	(855)	(909)	(693)	(710)
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	633,055	599,030
Allowance for credit losses	$ (5,543)	$ (5,768)	$ (4,399)	$ (4,516)